diff --git a/lightning/src/chain/channelmonitor.rs b/lightning/src/chain/channelmonitor.rs
index 47f5605ed..257d794ea 100644
--- a/lightning/src/chain/channelmonitor.rs
+++ b/lightning/src/chain/channelmonitor.rs
@@ -67,7 +67,7 @@ use crate::sync::{Mutex, LockTestExt};
 /// much smaller than a full [`ChannelMonitor`]. However, for large single commitment transaction
 /// updates (e.g. ones during which there are hundreds of HTLCs pending on the commitment
 /// transaction), a single update may reach upwards of 1 MiB in serialized size.
-#[derive(Clone, PartialEq, Eq)]
+#[derive(Clone, Debug, PartialEq, Eq)]
 #[must_use]
 pub struct ChannelMonitorUpdate {
 	pub(crate) updates: Vec<ChannelMonitorUpdateStep>,
@@ -487,7 +487,7 @@ impl_writeable_tlv_based_enum_upgradable!(OnchainEvent,
 
 );
 
-#[derive(Clone, PartialEq, Eq)]
+#[derive(Clone, Debug, PartialEq, Eq)]
 pub(crate) enum ChannelMonitorUpdateStep {
 	LatestHolderCommitmentTXInfo {
 		commitment_tx: HolderCommitmentTransaction,
diff --git a/lightning/src/ln/chan_utils.rs b/lightning/src/ln/chan_utils.rs
index 18048d8ef..968de7b43 100644
--- a/lightning/src/ln/chan_utils.rs
+++ b/lightning/src/ln/chan_utils.rs
@@ -450,7 +450,7 @@ pub fn derive_public_revocation_key<T: secp256k1::Verification>(secp_ctx: &Secp2
 /// channel basepoints via the new function, or they were obtained via
 /// CommitmentTransaction.trust().keys() because we trusted the source of the
 /// pre-calculated keys.
-#[derive(PartialEq, Eq, Clone)]
+#[derive(PartialEq, Eq, Clone, Debug)]
 pub struct TxCreationKeys {
 	/// The broadcaster's per-commitment public key which was used to derive the other keys.
 	pub per_commitment_point: PublicKey,
@@ -1028,7 +1028,7 @@ impl<'a> DirectedChannelTransactionParameters<'a> {
 /// Information needed to build and sign a holder's commitment transaction.
 ///
 /// The transaction is only signed once we are ready to broadcast.
-#[derive(Clone)]
+#[derive(Clone, Debug)]
 pub struct HolderCommitmentTransaction {
 	inner: CommitmentTransaction,
 	/// Our counterparty's signature for the transaction
@@ -1134,7 +1134,7 @@ impl HolderCommitmentTransaction {
 }
 
 /// A pre-built Bitcoin commitment transaction and its txid.
-#[derive(Clone)]
+#[derive(Clone, Debug)]
 pub struct BuiltCommitmentTransaction {
 	/// The commitment transaction
 	pub transaction: Transaction,
@@ -1305,7 +1305,7 @@ impl<'a> TrustedClosingTransaction<'a> {
 ///
 /// This class can be used inside a signer implementation to generate a signature given the relevant
 /// secret key.
-#[derive(Clone)]
+#[derive(Clone, Debug)]
 pub struct CommitmentTransaction {
 	commitment_number: u64,
 	to_broadcaster_value_sat: u64,
diff --git a/lightning/src/ln/chanmon_update_fail_tests.rs b/lightning/src/ln/chanmon_update_fail_tests.rs
index cd125c3fd..33f4bbc8c 100644
--- a/lightning/src/ln/chanmon_update_fail_tests.rs
+++ b/lightning/src/ln/chanmon_update_fail_tests.rs
@@ -3038,8 +3038,8 @@ fn test_blocked_chan_preimage_release() {
 	let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
 	let mut nodes = create_network(3, &node_cfgs, &node_chanmgrs);
 
-	create_announced_chan_between_nodes(&nodes, 0, 1).2;
-	create_announced_chan_between_nodes(&nodes, 1, 2).2;
+	create_announced_chan_between_nodes(&nodes, 0, 1);
+	let chan_id_2 = create_announced_chan_between_nodes(&nodes, 1, 2).2;
 
 	send_payment(&nodes[0], &[&nodes[1], &nodes[2]], 5_000_000);
 
@@ -3068,11 +3068,20 @@ fn test_blocked_chan_preimage_release() {
 	let as_htlc_fulfill_updates = get_htlc_update_msgs!(nodes[0], nodes[1].node.get_our_node_id());
 	nodes[1].node.handle_update_fulfill_htlc(&nodes[0].node.get_our_node_id(), &as_htlc_fulfill_updates.update_fulfill_htlcs[0]);
 	check_added_monitors(&nodes[1], 1); // We generate only a preimage monitor update
+	assert!(get_monitor!(nodes[1], chan_id_2).get_stored_preimages().contains_key(&payment_hash_2));
 	assert!(nodes[1].node.get_and_clear_pending_msg_events().is_empty());
 
-	// Finish the CS dance between nodes[0] and nodes[1].
-	do_commitment_signed_dance(&nodes[1], &nodes[0], &as_htlc_fulfill_updates.commitment_signed, false, false);
+	// Finish the CS dance between nodes[0] and nodes[1]. Note that until the event handling, the
+	// update_fulfill_htlc + CS is held, even though the preimage is already on disk for the
+	// channel.
+	nodes[1].node.handle_commitment_signed(&nodes[0].node.get_our_node_id(), &as_htlc_fulfill_updates.commitment_signed);
+	check_added_monitors(&nodes[1], 1);
+	let (a, raa) = do_main_commitment_signed_dance(&nodes[1], &nodes[0], false);
+	assert!(a.is_none());
+
+	nodes[1].node.handle_revoke_and_ack(&nodes[0].node.get_our_node_id(), &raa);
 	check_added_monitors(&nodes[1], 0);
+	assert!(nodes[1].node.get_and_clear_pending_msg_events().is_empty());
 
 	let events = nodes[1].node.get_and_clear_pending_events();
 	assert_eq!(events.len(), 3);
@@ -3080,8 +3089,8 @@ fn test_blocked_chan_preimage_release() {
 	if let Event::PaymentPathSuccessful { .. } = events[2] {} else { panic!(); }
 	if let Event::PaymentForwarded { .. } = events[1] {} else { panic!(); }
 
-	// The event processing should release the last RAA update.
-	check_added_monitors(&nodes[1], 1);
+	// The event processing should release the last RAA updates on both channels.
+	check_added_monitors(&nodes[1], 2);
 
 	// When we fetch the next update the message getter will generate the next update for nodes[2],
 	// generating a further monitor update.
@@ -3092,3 +3101,432 @@ fn test_blocked_chan_preimage_release() {
 	do_commitment_signed_dance(&nodes[2], &nodes[1], &bs_htlc_fulfill_updates.commitment_signed, false, false);
 	expect_payment_sent(&nodes[2], payment_preimage_2, None, true, true);
 }
+
+fn do_test_inverted_mon_completion_order(with_latest_manager: bool, complete_bc_commitment_dance: bool) {
+	// When we forward a payment and receive `update_fulfill_htlc`+`commitment_signed` messages
+	// from the downstream channel, we immediately claim the HTLC on the upstream channel, before
+	// even doing a `commitment_signed` dance on the downstream channel. This implies that our
+	// `ChannelMonitorUpdate`s are generated in the right order - first we ensure we'll get our
+	// money, then we write the update that resolves the downstream node claiming their money. This
+	// is safe as long as `ChannelMonitorUpdate`s complete in the order in which they are
+	// generated, but of course this may not be the case. For asynchronous update writes, we have
+	// to ensure monitor updates can block each other, preventing the inversion all together.
+	let chanmon_cfgs = create_chanmon_cfgs(3);
+	let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
+
+	let persister;
+	let new_chain_monitor;
+	let nodes_1_deserialized;
+
+	let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
+	let mut nodes = create_network(3, &node_cfgs, &node_chanmgrs);
+
+	let chan_id_ab = create_announced_chan_between_nodes(&nodes, 0, 1).2;
+	let chan_id_bc = create_announced_chan_between_nodes(&nodes, 1, 2).2;
+
+	// Route a payment from A, through B, to C, then claim it on C. Once we pass B the
+	// `update_fulfill_htlc` we have a monitor update for both of B's channels. We complete the one
+	// on the B<->C channel but leave the A<->B monitor update pending, then reload B.
+	let (payment_preimage, payment_hash, ..) = route_payment(&nodes[0], &[&nodes[1], &nodes[2]], 100_000);
+
+	let mon_ab = get_monitor!(nodes[1], chan_id_ab).encode();
+	let mut manager_b = Vec::new();
+	if !with_latest_manager {
+		manager_b = nodes[1].node.encode();
+	}
+
+	nodes[2].node.claim_funds(payment_preimage);
+	check_added_monitors(&nodes[2], 1);
+	expect_payment_claimed!(nodes[2], payment_hash, 100_000);
+
+	chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
+	let cs_updates = get_htlc_update_msgs(&nodes[2], &nodes[1].node.get_our_node_id());
+	nodes[1].node.handle_update_fulfill_htlc(&nodes[2].node.get_our_node_id(), &cs_updates.update_fulfill_htlcs[0]);
+
+	// B generates a new monitor update for the A <-> B channel, but doesn't send the new messages
+	// for it since the monitor update is marked in-progress.
+	check_added_monitors(&nodes[1], 1);
+	assert!(nodes[1].node.get_and_clear_pending_msg_events().is_empty());
+
+	// Now step the Commitment Signed Dance between B and C forward a bit (or fully), ensuring we
+	// won't get the preimage when the nodes reconnect and we have to get it from the
+	// ChannelMonitor.
+	nodes[1].node.handle_commitment_signed(&nodes[2].node.get_our_node_id(), &cs_updates.commitment_signed);
+	check_added_monitors(&nodes[1], 1);
+	if complete_bc_commitment_dance {
+		let (bs_revoke_and_ack, bs_commitment_signed) = get_revoke_commit_msgs!(nodes[1], nodes[2].node.get_our_node_id());
+		nodes[2].node.handle_revoke_and_ack(&nodes[1].node.get_our_node_id(), &bs_revoke_and_ack);
+		check_added_monitors(&nodes[2], 1);
+		nodes[2].node.handle_commitment_signed(&nodes[1].node.get_our_node_id(), &bs_commitment_signed);
+		check_added_monitors(&nodes[2], 1);
+		let cs_raa = get_event_msg!(nodes[2], MessageSendEvent::SendRevokeAndACK, nodes[1].node.get_our_node_id());
+
+		// At this point node B still hasn't persisted the `ChannelMonitorUpdate` with the
+		// preimage in the A <-> B channel, which will prevent it from persisting the
+		// `ChannelMonitorUpdate` for the B<->C channel here to avoid "losing" the preimage.
+		nodes[1].node.handle_revoke_and_ack(&nodes[2].node.get_our_node_id(), &cs_raa);
+		check_added_monitors(&nodes[1], 0);
+		assert!(nodes[1].node.get_and_clear_pending_msg_events().is_empty());
+	}
+
+	// Now reload node B
+	if with_latest_manager {
+		manager_b = nodes[1].node.encode();
+	}
+
+	let mon_bc = get_monitor!(nodes[1], chan_id_bc).encode();
+	reload_node!(nodes[1], &manager_b, &[&mon_ab, &mon_bc], persister, new_chain_monitor, nodes_1_deserialized);
+
+	nodes[0].node.peer_disconnected(&nodes[1].node.get_our_node_id());
+	nodes[2].node.peer_disconnected(&nodes[1].node.get_our_node_id());
+
+	if with_latest_manager {
+		// If we used the latest ChannelManager to reload from, we should have both channels still
+		// live. The B <-> C channel's final RAA ChannelMonitorUpdate must still be blocked as
+		// before - the ChannelMonitorUpdate for the A <-> B channel hasn't completed.
+		// When we call `timer_tick_occurred` we will get that monitor update back, which we'll
+		// complete after reconnecting to our peers.
+		persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
+		nodes[1].node.timer_tick_occurred();
+		check_added_monitors(&nodes[1], 1);
+		assert!(nodes[1].node.get_and_clear_pending_msg_events().is_empty());
+
+		// Now reconnect B to both A and C. If the B <-> C commitment signed dance wasn't run to
+		// the end go ahead and do that, though the
+		// `pending_responding_commitment_signed_dup_monitor` in `reconnect_args` indicates that we
+		// expect to *not* receive the final RAA ChannelMonitorUpdate.
+		if complete_bc_commitment_dance {
+			reconnect_nodes(ReconnectArgs::new(&nodes[1], &nodes[2]));
+		} else {
+			let mut reconnect_args = ReconnectArgs::new(&nodes[1], &nodes[2]);
+			reconnect_args.pending_responding_commitment_signed.1 = true;
+			reconnect_args.pending_responding_commitment_signed_dup_monitor.1 = true;
+			reconnect_args.pending_raa = (false, true);
+			reconnect_nodes(reconnect_args);
+		}
+
+		reconnect_nodes(ReconnectArgs::new(&nodes[0], &nodes[1]));
+
+		// (Finally) complete the A <-> B ChannelMonitorUpdate, ensuring the preimage is durably on
+		// disk in the proper ChannelMonitor, unblocking the B <-> C ChannelMonitor updating
+		// process.
+		let (outpoint, _, ab_update_id) = nodes[1].chain_monitor.latest_monitor_update_id.lock().unwrap().get(&chan_id_ab).unwrap().clone();
+		nodes[1].chain_monitor.chain_monitor.channel_monitor_updated(outpoint, ab_update_id).unwrap();
+
+		// When we fetch B's HTLC update messages next (now that the ChannelMonitorUpdate has
+		// completed), it will also release the final RAA ChannelMonitorUpdate on the B <-> C
+		// channel.
+	} else {
+		// If the ChannelManager used in the reload was stale, check that the B <-> C channel was
+		// closed.
+		//
+		// Note that this will also process the ChannelMonitorUpdates which were queued up when we
+		// reloaded the ChannelManager. This will re-emit the A<->B preimage as well as the B<->C
+		// force-closure ChannelMonitorUpdate. Once the A<->B preimage update completes, the claim
+		// commitment update will be allowed to go out.
+		check_added_monitors(&nodes[1], 0);
+		persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
+		persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
+		check_closed_event(&nodes[1], 1, ClosureReason::OutdatedChannelManager, false, &[nodes[2].node.get_our_node_id()], 100_000);
+		check_added_monitors(&nodes[1], 2);
+
+		nodes[1].node.timer_tick_occurred();
+		check_added_monitors(&nodes[1], 0);
+
+		// Don't bother to reconnect B to C - that channel has been closed. We don't need to
+		// exchange any messages here even though there's a pending commitment update because the
+		// ChannelMonitorUpdate hasn't yet completed.
+		reconnect_nodes(ReconnectArgs::new(&nodes[0], &nodes[1]));
+
+		let (outpoint, _, ab_update_id) = nodes[1].chain_monitor.latest_monitor_update_id.lock().unwrap().get(&chan_id_ab).unwrap().clone();
+		nodes[1].chain_monitor.chain_monitor.channel_monitor_updated(outpoint, ab_update_id).unwrap();
+
+		// The ChannelMonitorUpdate which was completed prior to the reconnect only contained the
+		// preimage (as it was a replay of the original ChannelMonitorUpdate from before we
+		// restarted). When we go to fetch the commitment transaction updates we'll poll the
+		// ChannelMonitorUpdate completion, then generate (and complete) a new ChannelMonitorUpdate
+		// with the actual commitment transaction, which will allow us to fulfill the HTLC with
+		// node A.
+	}
+
+	let bs_updates = get_htlc_update_msgs(&nodes[1], &nodes[0].node.get_our_node_id());
+	check_added_monitors(&nodes[1], 1);
+
+	nodes[0].node.handle_update_fulfill_htlc(&nodes[1].node.get_our_node_id(), &bs_updates.update_fulfill_htlcs[0]);
+	do_commitment_signed_dance(&nodes[0], &nodes[1], &bs_updates.commitment_signed, false, false);
+
+	expect_payment_forwarded!(nodes[1], &nodes[0], &nodes[2], Some(1_000), false, !with_latest_manager);
+
+	// Finally, check that the payment was, ultimately, seen as sent by node A.
+	expect_payment_sent(&nodes[0], payment_preimage, None, true, true);
+}
+
+#[test]
+fn test_inverted_mon_completion_order() {
+	do_test_inverted_mon_completion_order(true, true);
+	do_test_inverted_mon_completion_order(true, false);
+	do_test_inverted_mon_completion_order(false, true);
+	do_test_inverted_mon_completion_order(false, false);
+}
+
+fn do_test_durable_preimages_on_closed_channel(close_chans_before_reload: bool, close_only_a: bool, hold_post_reload_mon_update: bool) {
+	// Test that we can apply a `ChannelMonitorUpdate` with a payment preimage even if the channel
+	// is force-closed between when we generate the update on reload and when we go to handle the
+	// update or prior to generating the update at all.
+
+	if !close_chans_before_reload && close_only_a {
+		// If we're not closing, it makes no sense to "only close A"
+		panic!();
+	}
+
+	let chanmon_cfgs = create_chanmon_cfgs(3);
+	let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
+
+	let persister;
+	let new_chain_monitor;
+	let nodes_1_deserialized;
+
+	let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
+	let mut nodes = create_network(3, &node_cfgs, &node_chanmgrs);
+
+	let chan_id_ab = create_announced_chan_between_nodes(&nodes, 0, 1).2;
+	let chan_id_bc = create_announced_chan_between_nodes(&nodes, 1, 2).2;
+
+	// Route a payment from A, through B, to C, then claim it on C. Once we pass B the
+	// `update_fulfill_htlc` we have a monitor update for both of B's channels. We complete the one
+	// on the B<->C channel but leave the A<->B monitor update pending, then reload B.
+	let (payment_preimage, payment_hash, ..) = route_payment(&nodes[0], &[&nodes[1], &nodes[2]], 1_000_000);
+
+	let mon_ab = get_monitor!(nodes[1], chan_id_ab).encode();
+
+	nodes[2].node.claim_funds(payment_preimage);
+	check_added_monitors(&nodes[2], 1);
+	expect_payment_claimed!(nodes[2], payment_hash, 1_000_000);
+
+	chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
+	let cs_updates = get_htlc_update_msgs(&nodes[2], &nodes[1].node.get_our_node_id());
+	nodes[1].node.handle_update_fulfill_htlc(&nodes[2].node.get_our_node_id(), &cs_updates.update_fulfill_htlcs[0]);
+
+	// B generates a new monitor update for the A <-> B channel, but doesn't send the new messages
+	// for it since the monitor update is marked in-progress.
+	check_added_monitors(&nodes[1], 1);
+	assert!(nodes[1].node.get_and_clear_pending_msg_events().is_empty());
+
+	// Now step the Commitment Signed Dance between B and C forward a bit, ensuring we won't get
+	// the preimage when the nodes reconnect, at which point we have to ensure we get it from the
+	// ChannelMonitor.
+	nodes[1].node.handle_commitment_signed(&nodes[2].node.get_our_node_id(), &cs_updates.commitment_signed);
+	check_added_monitors(&nodes[1], 1);
+	let _ = get_revoke_commit_msgs!(nodes[1], nodes[2].node.get_our_node_id());
+
+	let mon_bc = get_monitor!(nodes[1], chan_id_bc).encode();
+
+	if close_chans_before_reload {
+		if !close_only_a {
+			chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
+			nodes[1].node.force_close_broadcasting_latest_txn(&chan_id_bc, &nodes[2].node.get_our_node_id()).unwrap();
+			check_closed_broadcast(&nodes[1], 1, true);
+			check_closed_event(&nodes[1], 1, ClosureReason::HolderForceClosed, false, &[nodes[2].node.get_our_node_id()], 100000);
+		}
+
+		chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
+		nodes[1].node.force_close_broadcasting_latest_txn(&chan_id_ab, &nodes[0].node.get_our_node_id()).unwrap();
+		check_closed_broadcast(&nodes[1], 1, true);
+		check_closed_event(&nodes[1], 1, ClosureReason::HolderForceClosed, false, &[nodes[0].node.get_our_node_id()], 100000);
+	}
+
+	// Now reload node B
+	let manager_b = nodes[1].node.encode();
+	reload_node!(nodes[1], &manager_b, &[&mon_ab, &mon_bc], persister, new_chain_monitor, nodes_1_deserialized);
+
+	nodes[0].node.peer_disconnected(&nodes[1].node.get_our_node_id());
+	nodes[2].node.peer_disconnected(&nodes[1].node.get_our_node_id());
+
+	if close_chans_before_reload {
+		// If the channels were already closed, B will rebroadcast its closing transactions here.
+		let bs_close_txn = nodes[1].tx_broadcaster.txn_broadcasted.lock().unwrap().split_off(0);
+		if close_only_a {
+			assert_eq!(bs_close_txn.len(), 2);
+		} else {
+			assert_eq!(bs_close_txn.len(), 3);
+		}
+	}
+
+	nodes[0].node.force_close_broadcasting_latest_txn(&chan_id_ab, &nodes[1].node.get_our_node_id()).unwrap();
+	check_closed_event(&nodes[0], 1, ClosureReason::HolderForceClosed, false, &[nodes[1].node.get_our_node_id()], 100000);
+	let as_closing_tx = nodes[0].tx_broadcaster.txn_broadcasted.lock().unwrap().split_off(0);
+	assert_eq!(as_closing_tx.len(), 1);
+
+	// In order to give A's closing transaction to B without processing background events first,
+	// use the _without_consistency_checks utility method. This is similar to connecting blocks
+	// during startup prior to the node being full initialized.
+	mine_transaction_without_consistency_checks(&nodes[1], &as_closing_tx[0]);
+
+	// After a timer tick a payment preimage ChannelMonitorUpdate is applied to the A<->B
+	// ChannelMonitor (possible twice), even though the channel has since been closed.
+	check_added_monitors(&nodes[1], 0);
+	let mons_added = if close_chans_before_reload { if !close_only_a { 4 } else { 3 } } else { 2 };
+	if hold_post_reload_mon_update {
+		for _ in 0..mons_added {
+			persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
+		}
+	}
+	nodes[1].node.timer_tick_occurred();
+	check_added_monitors(&nodes[1], mons_added);
+
+	// Finally, check that B created a payment preimage transaction and close out the payment.
+	let bs_txn = nodes[1].tx_broadcaster.txn_broadcasted.lock().unwrap().split_off(0);
+	assert_eq!(bs_txn.len(), if close_chans_before_reload && !close_only_a { 2 } else { 1 });
+	let bs_preimage_tx = &bs_txn[0];
+	check_spends!(bs_preimage_tx, as_closing_tx[0]);
+
+	if !close_chans_before_reload {
+		check_closed_broadcast(&nodes[1], 1, true);
+		check_closed_event(&nodes[1], 1, ClosureReason::CommitmentTxConfirmed, false, &[nodes[0].node.get_our_node_id()], 100000);
+	} else {
+		// While we forwarded the payment a while ago, we don't want to process events too early or
+		// we'll run background tasks we wanted to test individually.
+		expect_payment_forwarded!(nodes[1], nodes[0], nodes[2], None, true, !close_only_a);
+	}
+
+	mine_transactions(&nodes[0], &[&as_closing_tx[0], bs_preimage_tx]);
+	check_closed_broadcast(&nodes[0], 1, true);
+	expect_payment_sent(&nodes[0], payment_preimage, None, true, true);
+
+	if !close_chans_before_reload || close_only_a {
+		// Make sure the B<->C channel is still alive and well by sending a payment over it.
+		let mut reconnect_args = ReconnectArgs::new(&nodes[1], &nodes[2]);
+		reconnect_args.pending_responding_commitment_signed.1 = true;
+		if !close_chans_before_reload {
+			// TODO: If the A<->B channel was closed before we reloaded, the `ChannelManager`
+			// will consider the forwarded payment complete and allow the B<->C
+			// `ChannelMonitorUpdate` to complete, wiping the payment preimage. This should not
+			// be allowed, and needs fixing.
+			reconnect_args.pending_responding_commitment_signed_dup_monitor.1 = true;
+		}
+		reconnect_args.pending_raa.1 = true;
+
+		reconnect_nodes(reconnect_args);
+		let (outpoint, ab_update_id, _) = nodes[1].chain_monitor.latest_monitor_update_id.lock().unwrap().get(&chan_id_ab).unwrap().clone();
+		nodes[1].chain_monitor.chain_monitor.force_channel_monitor_updated(outpoint, ab_update_id);
+		expect_payment_forwarded!(nodes[1], nodes[0], nodes[2], Some(1000), true, false);
+		if !close_chans_before_reload {
+			// Once we call `process_pending_events` the final `ChannelMonitor` for the B<->C
+			// channel will fly, removing the payment preimage from it.
+			check_added_monitors(&nodes[1], 1);
+		}
+		assert!(nodes[1].node.get_and_clear_pending_events().is_empty());
+		send_payment(&nodes[1], &[&nodes[2]], 100_000);
+	}
+}
+
+#[test]
+fn test_durable_preimages_on_closed_channel() {
+	do_test_durable_preimages_on_closed_channel(true, true, true);
+	do_test_durable_preimages_on_closed_channel(true, true, false);
+	do_test_durable_preimages_on_closed_channel(true, false, true);
+	do_test_durable_preimages_on_closed_channel(true, false, false);
+	do_test_durable_preimages_on_closed_channel(false, false, true);
+	do_test_durable_preimages_on_closed_channel(false, false, false);
+}
+
+fn do_test_reload_mon_update_completion_actions(close_during_reload: bool) {
+	// Test that if a `ChannelMonitorUpdate` completes but a `ChannelManager` isn't serialized
+	// before restart we run the monitor update completion action on startup.
+	let chanmon_cfgs = create_chanmon_cfgs(3);
+	let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
+
+	let persister;
+	let new_chain_monitor;
+	let nodes_1_deserialized;
+
+	let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
+	let mut nodes = create_network(3, &node_cfgs, &node_chanmgrs);
+
+	let chan_id_ab = create_announced_chan_between_nodes(&nodes, 0, 1).2;
+	let chan_id_bc = create_announced_chan_between_nodes(&nodes, 1, 2).2;
+
+	// Route a payment from A, through B, to C, then claim it on C. Once we pass B the
+	// `update_fulfill_htlc`+`commitment_signed` we have a monitor update for both of B's channels.
+	// We complete the commitment signed dance on the B<->C channel but leave the A<->B monitor
+	// update pending, then reload B. At that point, the final monitor update on the B<->C channel
+	// is still pending because it can't fly until the preimage is persisted on the A<->B monitor.
+	let (payment_preimage, payment_hash, ..) = route_payment(&nodes[0], &[&nodes[1], &nodes[2]], 1_000_000);
+
+	nodes[2].node.claim_funds(payment_preimage);
+	check_added_monitors(&nodes[2], 1);
+	expect_payment_claimed!(nodes[2], payment_hash, 1_000_000);
+
+	chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
+	let cs_updates = get_htlc_update_msgs(&nodes[2], &nodes[1].node.get_our_node_id());
+	nodes[1].node.handle_update_fulfill_htlc(&nodes[2].node.get_our_node_id(), &cs_updates.update_fulfill_htlcs[0]);
+
+	// B generates a new monitor update for the A <-> B channel, but doesn't send the new messages
+	// for it since the monitor update is marked in-progress.
+	check_added_monitors(&nodes[1], 1);
+	assert!(nodes[1].node.get_and_clear_pending_msg_events().is_empty());
+
+	// Now step the Commitment Signed Dance between B and C and check that after the final RAA B
+	// doesn't let the preimage-removing monitor update fly.
+	nodes[1].node.handle_commitment_signed(&nodes[2].node.get_our_node_id(), &cs_updates.commitment_signed);
+	check_added_monitors(&nodes[1], 1);
+	let (bs_raa, bs_cs) = get_revoke_commit_msgs!(nodes[1], nodes[2].node.get_our_node_id());
+
+	nodes[2].node.handle_revoke_and_ack(&nodes[1].node.get_our_node_id(), &bs_raa);
+	check_added_monitors(&nodes[2], 1);
+	nodes[2].node.handle_commitment_signed(&nodes[1].node.get_our_node_id(), &bs_cs);
+	check_added_monitors(&nodes[2], 1);
+
+	let cs_final_raa = get_event_msg!(nodes[2], MessageSendEvent::SendRevokeAndACK, nodes[1].node.get_our_node_id());
+	nodes[1].node.handle_revoke_and_ack(&nodes[2].node.get_our_node_id(), &cs_final_raa);
+	check_added_monitors(&nodes[1], 0);
+
+	// Finally, reload node B and check that after we call `process_pending_events` once we realize
+	// we've completed the A<->B preimage-including monitor update and so can release the B<->C
+	// preimage-removing monitor update.
+	let mon_ab = get_monitor!(nodes[1], chan_id_ab).encode();
+	let mon_bc = get_monitor!(nodes[1], chan_id_bc).encode();
+	let manager_b = nodes[1].node.encode();
+	reload_node!(nodes[1], &manager_b, &[&mon_ab, &mon_bc], persister, new_chain_monitor, nodes_1_deserialized);
+
+	if close_during_reload {
+		// Test that we still free the B<->C channel if the A<->B channel closed while we reloaded
+		// (as learned about during the on-reload block connection).
+		nodes[0].node.force_close_broadcasting_latest_txn(&chan_id_ab, &nodes[1].node.get_our_node_id()).unwrap();
+		check_added_monitors!(nodes[0], 1);
+		check_closed_broadcast!(nodes[0], true);
+		check_closed_event(&nodes[0], 1, ClosureReason::HolderForceClosed, false, &[nodes[1].node.get_our_node_id()], 100_000);
+		let as_closing_tx = nodes[0].tx_broadcaster.txn_broadcasted.lock().unwrap().split_off(0);
+		mine_transaction_without_consistency_checks(&nodes[1], &as_closing_tx[0]);
+	}
+
+	let bc_update_id = nodes[1].chain_monitor.latest_monitor_update_id.lock().unwrap().get(&chan_id_bc).unwrap().2;
+	let mut events = nodes[1].node.get_and_clear_pending_events();
+	assert_eq!(events.len(), if close_during_reload { 2 } else { 1 });
+	expect_payment_forwarded(events.pop().unwrap(), &nodes[1], &nodes[0], &nodes[2], Some(1000), close_during_reload, false);
+	if close_during_reload {
+		match events[0] {
+			Event::ChannelClosed { .. } => {},
+			_ => panic!(),
+		}
+		check_closed_broadcast!(nodes[1], true);
+	}
+
+	// Once we run event processing the monitor should free, check that it was indeed the B<->C
+	// channel which was updated.
+	check_added_monitors(&nodes[1], if close_during_reload { 2 } else { 1 });
+	let post_ev_bc_update_id = nodes[1].chain_monitor.latest_monitor_update_id.lock().unwrap().get(&chan_id_bc).unwrap().2;
+	assert!(bc_update_id != post_ev_bc_update_id);
+
+	// Finally, check that there's nothing left to do on B<->C reconnect and the channel operates
+	// fine.
+	nodes[2].node.peer_disconnected(&nodes[1].node.get_our_node_id());
+	reconnect_nodes(ReconnectArgs::new(&nodes[1], &nodes[2]));
+	send_payment(&nodes[1], &[&nodes[2]], 100_000);
+}
+
+#[test]
+fn test_reload_mon_update_completion_actions() {
+	do_test_reload_mon_update_completion_actions(true);
+	do_test_reload_mon_update_completion_actions(false);
+}
diff --git a/lightning/src/ln/channelmanager.rs b/lightning/src/ln/channelmanager.rs
index ed00282fb..e2d7c90f7 100644
--- a/lightning/src/ln/channelmanager.rs
+++ b/lightning/src/ln/channelmanager.rs
@@ -177,7 +177,7 @@ pub(super) enum HTLCForwardInfo {
 }
 
 /// Tracks the inbound corresponding to an outbound HTLC
-#[derive(Clone, Hash, PartialEq, Eq)]
+#[derive(Clone, Debug, Hash, PartialEq, Eq)]
 pub(crate) struct HTLCPreviousHopData {
 	// Note that this may be an outbound SCID alias for the associated channel.
 	short_channel_id: u64,
@@ -283,7 +283,7 @@ impl Readable for InterceptId {
 	}
 }
 
-#[derive(Clone, Copy, PartialEq, Eq, Hash)]
+#[derive(Clone, Copy, Debug, PartialEq, Eq, Hash)]
 /// Uniquely describes an HTLC by its source. Just the guaranteed-unique subset of [`HTLCSource`].
 pub(crate) enum SentHTLCId {
 	PreviousHopData { short_channel_id: u64, htlc_id: u64 },
@@ -314,7 +314,7 @@ impl_writeable_tlv_based_enum!(SentHTLCId,
 
 /// Tracks the inbound corresponding to an outbound HTLC
 #[allow(clippy::derive_hash_xor_eq)] // Our Hash is faithful to the data, we just don't have SecretKey::hash
-#[derive(Clone, PartialEq, Eq)]
+#[derive(Clone, Debug, PartialEq, Eq)]
 pub(crate) enum HTLCSource {
 	PreviousHopData(HTLCPreviousHopData),
 	OutboundRoute {
@@ -656,7 +656,6 @@ pub(crate) enum RAAMonitorUpdateBlockingAction {
 }
 
 impl RAAMonitorUpdateBlockingAction {
-	#[allow(unused)]
 	fn from_prev_hop_data(prev_hop: &HTLCPreviousHopData) -> Self {
 		Self::ForwardedPaymentInboundClaim {
 			channel_id: prev_hop.outpoint.to_channel_id(),
@@ -5175,11 +5174,17 @@ where
 		self.pending_outbound_payments.finalize_claims(sources, &self.pending_events);
 	}
 
-	fn claim_funds_internal(&self, source: HTLCSource, payment_preimage: PaymentPreimage, forwarded_htlc_value_msat: Option<u64>, from_onchain: bool, next_channel_outpoint: OutPoint) {
+	fn claim_funds_internal(&self, source: HTLCSource, payment_preimage: PaymentPreimage,
+		forwarded_htlc_value_msat: Option<u64>, from_onchain: bool,
+		next_channel_counterparty_node_id: Option<PublicKey>, next_channel_outpoint: OutPoint
+	) {
 		match source {
 			HTLCSource::OutboundRoute { session_priv, payment_id, path, .. } => {
 				debug_assert!(self.background_events_processed_since_startup.load(Ordering::Acquire),
 					"We don't support claim_htlc claims during startup - monitors may not be available yet");
+				if let Some(pubkey) = next_channel_counterparty_node_id {
+					debug_assert_eq!(pubkey, path.hops[0].pubkey);
+				}
 				let ev_completion_action = EventCompletionAction::ReleaseRAAChannelMonitorUpdate {
 					channel_funding_outpoint: next_channel_outpoint,
 					counterparty_node_id: path.hops[0].pubkey,
@@ -5190,6 +5195,7 @@ where
 			},
 			HTLCSource::PreviousHopData(hop_data) => {
 				let prev_outpoint = hop_data.outpoint;
+				let completed_blocker = RAAMonitorUpdateBlockingAction::from_prev_hop_data(&hop_data);
 				let res = self.claim_funds_from_hop(hop_data, payment_preimage,
 					|htlc_claim_value_msat| {
 						if let Some(forwarded_htlc_value) = forwarded_htlc_value_msat {
@@ -5205,7 +5211,17 @@ where
 									next_channel_id: Some(next_channel_outpoint.to_channel_id()),
 									outbound_amount_forwarded_msat: forwarded_htlc_value_msat,
 								},
-								downstream_counterparty_and_funding_outpoint: None,
+								downstream_counterparty_and_funding_outpoint:
+									if let Some(node_id) = next_channel_counterparty_node_id {
+										Some((node_id, next_channel_outpoint, completed_blocker))
+									} else {
+										// We can only get `None` here if we are processing a
+										// `ChannelMonitor`-originated event, in which case we
+										// don't care about ensuring we wake the downstream
+										// channel's monitor updating - the channel is already
+										// closed.
+										None
+									},
 							})
 						} else { None }
 					});
@@ -6044,6 +6060,17 @@ where
 				hash_map::Entry::Occupied(mut chan_phase_entry) => {
 					if let ChannelPhase::Funded(chan) = chan_phase_entry.get_mut() {
 						let res = try_chan_phase_entry!(self, chan.update_fulfill_htlc(&msg), chan_phase_entry);
+						if let HTLCSource::PreviousHopData(prev_hop) = &res.0 {
+							peer_state.actions_blocking_raa_monitor_updates.entry(msg.channel_id)
+								.or_insert_with(Vec::new)
+								.push(RAAMonitorUpdateBlockingAction::from_prev_hop_data(&prev_hop));
+						}
+						// Note that we do not need to push an `actions_blocking_raa_monitor_updates`
+						// entry here, even though we *do* need to block the next RAA monitor update.
+						// We do this instead in the `claim_funds_internal` by attaching a
+						// `ReleaseRAAChannelMonitorUpdate` action to the event generated when the
+						// outbound HTLC is claimed. This is guaranteed to all complete before we
+						// process the RAA as messages are processed from single peers serially.
 						funding_txo = chan.context.get_funding_txo().expect("We won't accept a fulfill until funded");
 						res
 					} else {
@@ -6054,7 +6081,7 @@ where
 				hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close(format!("Got a message for a channel from the wrong node! No such channel for the passed counterparty_node_id {}", counterparty_node_id), msg.channel_id))
 			}
 		};
-		self.claim_funds_internal(htlc_source, msg.payment_preimage.clone(), Some(forwarded_htlc_value), false, funding_txo);
+		self.claim_funds_internal(htlc_source, msg.payment_preimage.clone(), Some(forwarded_htlc_value), false, Some(*counterparty_node_id), funding_txo);
 		Ok(())
 	}
 
@@ -6256,6 +6283,23 @@ where
 		})
 	}
 
+	#[cfg(any(test, feature = "_test_utils"))]
+	pub(crate) fn test_raa_monitor_updates_held(&self,
+		counterparty_node_id: PublicKey, channel_id: ChannelId
+	) -> bool {
+		let per_peer_state = self.per_peer_state.read().unwrap();
+		if let Some(peer_state_mtx) = per_peer_state.get(&counterparty_node_id) {
+			let mut peer_state_lck = peer_state_mtx.lock().unwrap();
+			let peer_state = &mut *peer_state_lck;
+
+			if let Some(chan) = peer_state.channel_by_id.get(&channel_id) {
+				return self.raa_monitor_updates_held(&peer_state.actions_blocking_raa_monitor_updates,
+					chan.context().get_funding_txo().unwrap(), counterparty_node_id);
+			}
+		}
+		false
+	}
+
 	fn internal_revoke_and_ack(&self, counterparty_node_id: &PublicKey, msg: &msgs::RevokeAndACK) -> Result<(), MsgHandleErrInternal> {
 		let (htlcs_to_fail, res) = {
 			let per_peer_state = self.per_peer_state.read().unwrap();
@@ -6477,8 +6521,8 @@ where
 				match monitor_event {
 					MonitorEvent::HTLCEvent(htlc_update) => {
 						if let Some(preimage) = htlc_update.payment_preimage {
-							log_trace!(self.logger, "Claiming HTLC with preimage {} from our monitor", &preimage);
-							self.claim_funds_internal(htlc_update.source, preimage, htlc_update.htlc_value_satoshis.map(|v| v * 1000), true, funding_outpoint);
+							log_trace!(self.logger, "Claiming HTLC with preimage {} from our monitor", preimage);
+							self.claim_funds_internal(htlc_update.source, preimage, htlc_update.htlc_value_satoshis.map(|v| v * 1000), true, counterparty_node_id, funding_outpoint);
 						} else {
 							log_trace!(self.logger, "Failing HTLC with hash {} from our monitor", &htlc_update.payment_hash);
 							let receiver = HTLCDestination::NextHopChannel { node_id: counterparty_node_id, channel_id: funding_outpoint.to_channel_id() };
@@ -9298,6 +9342,7 @@ where
 									// downstream chan is closed (because we don't have a
 									// channel_id -> peer map entry).
 									counterparty_opt.is_none(),
+									counterparty_opt.cloned().or(monitor.get_counterparty_node_id()),
 									monitor.get_funding_txo().0))
 							} else { None }
 						} else {
@@ -9576,12 +9621,12 @@ where
 			channel_manager.fail_htlc_backwards_internal(&source, &payment_hash, &reason, receiver);
 		}
 
-		for (source, preimage, downstream_value, downstream_closed, downstream_funding) in pending_claims_to_replay {
+		for (source, preimage, downstream_value, downstream_closed, downstream_node_id, downstream_funding) in pending_claims_to_replay {
 			// We use `downstream_closed` in place of `from_onchain` here just as a guess - we
 			// don't remember in the `ChannelMonitor` where we got a preimage from, but if the
 			// channel is closed we just assume that it probably came from an on-chain claim.
 			channel_manager.claim_funds_internal(source, preimage, Some(downstream_value),
-				downstream_closed, downstream_funding);
+				downstream_closed, downstream_node_id, downstream_funding);
 		}
 
 		//TODO: Broadcast channel update for closed channels, but only after we've made a
diff --git a/lightning/src/ln/functional_test_utils.rs b/lightning/src/ln/functional_test_utils.rs
index fbfa7e5b6..f6684485d 100644
--- a/lightning/src/ln/functional_test_utils.rs
+++ b/lightning/src/ln/functional_test_utils.rs
@@ -17,7 +17,7 @@ use crate::chain::transaction::OutPoint;
 use crate::events::{ClaimedHTLC, ClosureReason, Event, HTLCDestination, MessageSendEvent, MessageSendEventsProvider, PathFailure, PaymentPurpose, PaymentFailureReason};
 use crate::events::bump_transaction::{BumpTransactionEventHandler, Wallet, WalletSource};
 use crate::ln::{ChannelId, PaymentPreimage, PaymentHash, PaymentSecret};
-use crate::ln::channelmanager::{self, AChannelManager, ChainParameters, ChannelManager, ChannelManagerReadArgs, RAACommitmentOrder, PaymentSendFailure, RecipientOnionFields, PaymentId, MIN_CLTV_EXPIRY_DELTA};
+use crate::ln::channelmanager::{AChannelManager, ChainParameters, ChannelManager, ChannelManagerReadArgs, RAACommitmentOrder, PaymentSendFailure, RecipientOnionFields, PaymentId, MIN_CLTV_EXPIRY_DELTA};
 use crate::routing::gossip::{P2PGossipSync, NetworkGraph, NetworkUpdate};
 use crate::routing::router::{self, PaymentParameters, Route, RouteParameters};
 use crate::ln::features::InitFeatures;
@@ -73,6 +73,20 @@ pub fn mine_transactions<'a, 'b, 'c, 'd>(node: &'a Node<'b, 'c, 'd>, txn: &[&Tra
 	let height = node.best_block_info().1 + 1;
 	confirm_transactions_at(node, txn, height);
 }
+/// Mine a single block containing the given transaction without extra consistency checks which may
+/// impact ChannelManager state.
+pub fn mine_transaction_without_consistency_checks<'a, 'b, 'c, 'd>(node: &'a Node<'b, 'c, 'd>, tx: &Transaction) {
+	let height = node.best_block_info().1 + 1;
+	let mut block = Block {
+		header: BlockHeader { version: 0x20000000, prev_blockhash: node.best_block_hash(), merkle_root: TxMerkleNode::all_zeros(), time: height, bits: 42, nonce: 42 },
+		txdata: Vec::new(),
+	};
+	for _ in 0..*node.network_chan_count.borrow() { // Make sure we don't end up with channels at the same short id by offsetting by chan_count
+		block.txdata.push(Transaction { version: 0, lock_time: PackedLockTime::ZERO, input: Vec::new(), output: Vec::new() });
+	}
+	block.txdata.push((*tx).clone());
+	do_connect_block_without_consistency_checks(node, block, false);
+}
 /// Mine the given transaction at the given height, mining blocks as required to build to that
 /// height
 ///
@@ -211,16 +225,16 @@ pub fn connect_blocks<'a, 'b, 'c, 'd>(node: &'a Node<'b, 'c, 'd>, depth: u32) ->
 	assert!(depth >= 1);
 	for i in 1..depth {
 		let prev_blockhash = block.header.block_hash();
-		do_connect_block(node, block, skip_intermediaries);
+		do_connect_block_with_consistency_checks(node, block, skip_intermediaries);
 		block = create_dummy_block(prev_blockhash, height + i, Vec::new());
 	}
 	let hash = block.header.block_hash();
-	do_connect_block(node, block, false);
+	do_connect_block_with_consistency_checks(node, block, false);
 	hash
 }
 
 pub fn connect_block<'a, 'b, 'c, 'd>(node: &'a Node<'b, 'c, 'd>, block: &Block) {
-	do_connect_block(node, block.clone(), false);
+	do_connect_block_with_consistency_checks(node, block.clone(), false);
 }
 
 fn call_claimable_balances<'a, 'b, 'c, 'd>(node: &'a Node<'b, 'c, 'd>) {
@@ -230,8 +244,14 @@ fn call_claimable_balances<'a, 'b, 'c, 'd>(node: &'a Node<'b, 'c, 'd>) {
 	}
 }
 
-fn do_connect_block<'a, 'b, 'c, 'd>(node: &'a Node<'b, 'c, 'd>, block: Block, skip_intermediaries: bool) {
+fn do_connect_block_with_consistency_checks<'a, 'b, 'c, 'd>(node: &'a Node<'b, 'c, 'd>, block: Block, skip_intermediaries: bool) {
 	call_claimable_balances(node);
+	do_connect_block_without_consistency_checks(node, block, skip_intermediaries);
+	call_claimable_balances(node);
+	node.node.test_process_background_events();
+}
+
+fn do_connect_block_without_consistency_checks<'a, 'b, 'c, 'd>(node: &'a Node<'b, 'c, 'd>, block: Block, skip_intermediaries: bool) {
 	let height = node.best_block_info().1 + 1;
 	#[cfg(feature = "std")] {
 		eprintln!("Connecting block using Block Connection Style: {:?}", *node.connect_style.borrow());
@@ -286,8 +306,6 @@ fn do_connect_block<'a, 'b, 'c, 'd>(node: &'a Node<'b, 'c, 'd>, block: Block, sk
 			}
 		}
 	}
-	call_claimable_balances(node);
-	node.node.test_process_background_events();
 
 	for tx in &block.txdata {
 		for input in &tx.input {
@@ -1772,20 +1790,7 @@ pub fn do_commitment_signed_dance(node_a: &Node<'_, '_, '_>, node_b: &Node<'_, '
 	check_added_monitors!(node_a, 1);
 
 	// If this commitment signed dance was due to a claim, don't check for an RAA monitor update.
-	let got_claim = node_a.node.pending_events.lock().unwrap().iter().any(|(ev, action)| {
-		let matching_action = if let Some(channelmanager::EventCompletionAction::ReleaseRAAChannelMonitorUpdate
-			{ channel_funding_outpoint, counterparty_node_id }) = action
-		{
-			if channel_funding_outpoint.to_channel_id() == commitment_signed.channel_id {
-				assert_eq!(*counterparty_node_id, node_b.node.get_our_node_id());
-				true
-			} else { false }
-		} else { false };
-		if matching_action {
-			if let Event::PaymentSent { .. } = ev {} else { panic!(); }
-		}
-		matching_action
-	});
+	let got_claim = node_a.node.test_raa_monitor_updates_held(node_b.node.get_our_node_id(), commitment_signed.channel_id);
 	if fail_backwards { assert!(!got_claim); }
 	commitment_signed_dance!(node_a, node_b, (), fail_backwards, true, false, got_claim);
 
@@ -2000,29 +2005,38 @@ macro_rules! expect_payment_path_successful {
 	}
 }
 
+pub fn expect_payment_forwarded<CM: AChannelManager, H: NodeHolder<CM=CM>>(
+	event: Event, node: &H, prev_node: &H, next_node: &H, expected_fee: Option<u64>,
+	upstream_force_closed: bool, downstream_force_closed: bool
+) {
+	match event {
+		Event::PaymentForwarded {
+			fee_earned_msat, prev_channel_id, claim_from_onchain_tx, next_channel_id,
+			outbound_amount_forwarded_msat: _
+		} => {
+			assert_eq!(fee_earned_msat, expected_fee);
+			if !upstream_force_closed {
+				// Is the event prev_channel_id in one of the channels between the two nodes?
+				assert!(node.node().list_channels().iter().any(|x| x.counterparty.node_id == prev_node.node().get_our_node_id() && x.channel_id == prev_channel_id.unwrap()));
+			}
+			// We check for force closures since a force closed channel is removed from the
+			// node's channel list
+			if !downstream_force_closed {
+				assert!(node.node().list_channels().iter().any(|x| x.counterparty.node_id == next_node.node().get_our_node_id() && x.channel_id == next_channel_id.unwrap()));
+			}
+			assert_eq!(claim_from_onchain_tx, downstream_force_closed);
+		},
+		_ => panic!("Unexpected event"),
+	}
+}
+
 macro_rules! expect_payment_forwarded {
 	($node: expr, $prev_node: expr, $next_node: expr, $expected_fee: expr, $upstream_force_closed: expr, $downstream_force_closed: expr) => {
-		let events = $node.node.get_and_clear_pending_events();
+		let mut events = $node.node.get_and_clear_pending_events();
 		assert_eq!(events.len(), 1);
-		match events[0] {
-			Event::PaymentForwarded {
-				fee_earned_msat, prev_channel_id, claim_from_onchain_tx, next_channel_id,
-				outbound_amount_forwarded_msat: _
-			} => {
-				assert_eq!(fee_earned_msat, $expected_fee);
-				if fee_earned_msat.is_some() {
-					// Is the event prev_channel_id in one of the channels between the two nodes?
-					assert!($node.node.list_channels().iter().any(|x| x.counterparty.node_id == $prev_node.node.get_our_node_id() && x.channel_id == prev_channel_id.unwrap()));
-				}
-				// We check for force closures since a force closed channel is removed from the
-				// node's channel list
-				if !$downstream_force_closed {
-					assert!($node.node.list_channels().iter().any(|x| x.counterparty.node_id == $next_node.node.get_our_node_id() && x.channel_id == next_channel_id.unwrap()));
-				}
-				assert_eq!(claim_from_onchain_tx, $downstream_force_closed);
-			},
-			_ => panic!("Unexpected event"),
-		}
+		$crate::ln::functional_test_utils::expect_payment_forwarded(
+			events.pop().unwrap(), &$node, &$prev_node, &$next_node, $expected_fee,
+			$upstream_force_closed, $downstream_force_closed);
 	}
 }
 
@@ -2399,7 +2413,7 @@ pub fn pass_claimed_payment_along_route<'a, 'b, 'c>(origin_node: &Node<'a, 'b, '
 						}
 					};
 					if $idx == 1 { fee += expected_extra_fees[i]; }
-					expect_payment_forwarded!($node, $next_node, $prev_node, Some(fee as u64), false, false);
+					expect_payment_forwarded!(*$node, $next_node, $prev_node, Some(fee as u64), false, false);
 					expected_total_fee_msat += fee as u64;
 					check_added_monitors!($node, 1);
 					let new_next_msgs = if $new_msgs {
@@ -3030,7 +3044,11 @@ pub struct ReconnectArgs<'a, 'b, 'c, 'd> {
 	pub node_a: &'a Node<'b, 'c, 'd>,
 	pub node_b: &'a Node<'b, 'c, 'd>,
 	pub send_channel_ready: (bool, bool),
-	pub pending_htlc_adds: (i64, i64),
+	pub pending_responding_commitment_signed: (bool, bool),
+	/// Indicates that the pending responding commitment signed will be a dup for the recipient,
+	/// and no monitor update is expected
+	pub pending_responding_commitment_signed_dup_monitor: (bool, bool),
+	pub pending_htlc_adds: (usize, usize),
 	pub pending_htlc_claims: (usize, usize),
 	pub pending_htlc_fails: (usize, usize),
 	pub pending_cell_htlc_claims: (usize, usize),
@@ -3044,6 +3062,8 @@ impl<'a, 'b, 'c, 'd> ReconnectArgs<'a, 'b, 'c, 'd> {
 			node_a,
 			node_b,
 			send_channel_ready: (false, false),
+			pending_responding_commitment_signed: (false, false),
+			pending_responding_commitment_signed_dup_monitor: (false, false),
 			pending_htlc_adds: (0, 0),
 			pending_htlc_claims: (0, 0),
 			pending_htlc_fails: (0, 0),
@@ -3059,7 +3079,8 @@ impl<'a, 'b, 'c, 'd> ReconnectArgs<'a, 'b, 'c, 'd> {
 pub fn reconnect_nodes<'a, 'b, 'c, 'd>(args: ReconnectArgs<'a, 'b, 'c, 'd>) {
 	let ReconnectArgs {
 		node_a, node_b, send_channel_ready, pending_htlc_adds, pending_htlc_claims, pending_htlc_fails,
-		pending_cell_htlc_claims, pending_cell_htlc_fails, pending_raa
+		pending_cell_htlc_claims, pending_cell_htlc_fails, pending_raa,
+		pending_responding_commitment_signed, pending_responding_commitment_signed_dup_monitor,
 	} = args;
 	node_a.node.peer_connected(&node_b.node.get_our_node_id(), &msgs::Init {
 		features: node_b.node.init_features(), networks: None, remote_network_address: None
@@ -3144,13 +3165,12 @@ pub fn reconnect_nodes<'a, 'b, 'c, 'd>(args: ReconnectArgs<'a, 'b, 'c, 'd>) {
 		} else {
 			assert!(chan_msgs.1.is_none());
 		}
-		if pending_htlc_adds.0 != 0 || pending_htlc_claims.0 != 0 || pending_htlc_fails.0 != 0 || pending_cell_htlc_claims.0 != 0 || pending_cell_htlc_fails.0 != 0 {
+		if pending_htlc_adds.0 != 0 || pending_htlc_claims.0 != 0 || pending_htlc_fails.0 != 0 ||
+			pending_cell_htlc_claims.0 != 0 || pending_cell_htlc_fails.0 != 0 ||
+			pending_responding_commitment_signed.0
+		{
 			let commitment_update = chan_msgs.2.unwrap();
-			if pending_htlc_adds.0 != -1 { // We use -1 to denote a response commitment_signed
-				assert_eq!(commitment_update.update_add_htlcs.len(), pending_htlc_adds.0 as usize);
-			} else {
-				assert!(commitment_update.update_add_htlcs.is_empty());
-			}
+			assert_eq!(commitment_update.update_add_htlcs.len(), pending_htlc_adds.0);
 			assert_eq!(commitment_update.update_fulfill_htlcs.len(), pending_htlc_claims.0 + pending_cell_htlc_claims.0);
 			assert_eq!(commitment_update.update_fail_htlcs.len(), pending_htlc_fails.0 + pending_cell_htlc_fails.0);
 			assert!(commitment_update.update_fail_malformed_htlcs.is_empty());
@@ -3164,7 +3184,7 @@ pub fn reconnect_nodes<'a, 'b, 'c, 'd>(args: ReconnectArgs<'a, 'b, 'c, 'd>) {
 				node_a.node.handle_update_fail_htlc(&node_b.node.get_our_node_id(), &update_fail);
 			}
 
-			if pending_htlc_adds.0 != -1 { // We use -1 to denote a response commitment_signed
+			if !pending_responding_commitment_signed.0 {
 				commitment_signed_dance!(node_a, node_b, commitment_update.commitment_signed, false);
 			} else {
 				node_a.node.handle_commitment_signed(&node_b.node.get_our_node_id(), &commitment_update.commitment_signed);
@@ -3173,7 +3193,7 @@ pub fn reconnect_nodes<'a, 'b, 'c, 'd>(args: ReconnectArgs<'a, 'b, 'c, 'd>) {
 				// No commitment_signed so get_event_msg's assert(len == 1) passes
 				node_b.node.handle_revoke_and_ack(&node_a.node.get_our_node_id(), &as_revoke_and_ack);
 				assert!(node_b.node.get_and_clear_pending_msg_events().is_empty());
-				check_added_monitors!(node_b, 1);
+				check_added_monitors!(node_b, if pending_responding_commitment_signed_dup_monitor.0 { 0 } else { 1 });
 			}
 		} else {
 			assert!(chan_msgs.2.is_none());
@@ -3203,11 +3223,12 @@ pub fn reconnect_nodes<'a, 'b, 'c, 'd>(args: ReconnectArgs<'a, 'b, 'c, 'd>) {
 		} else {
 			assert!(chan_msgs.1.is_none());
 		}
-		if pending_htlc_adds.1 != 0 || pending_htlc_claims.1 != 0 || pending_htlc_fails.1 != 0 || pending_cell_htlc_claims.1 != 0 || pending_cell_htlc_fails.1 != 0 {
+		if pending_htlc_adds.1 != 0 || pending_htlc_claims.1 != 0 || pending_htlc_fails.1 != 0 ||
+			pending_cell_htlc_claims.1 != 0 || pending_cell_htlc_fails.1 != 0 ||
+			pending_responding_commitment_signed.1
+		{
 			let commitment_update = chan_msgs.2.unwrap();
-			if pending_htlc_adds.1 != -1 { // We use -1 to denote a response commitment_signed
-				assert_eq!(commitment_update.update_add_htlcs.len(), pending_htlc_adds.1 as usize);
-			}
+			assert_eq!(commitment_update.update_add_htlcs.len(), pending_htlc_adds.1);
 			assert_eq!(commitment_update.update_fulfill_htlcs.len(), pending_htlc_claims.1 + pending_cell_htlc_claims.1);
 			assert_eq!(commitment_update.update_fail_htlcs.len(), pending_htlc_fails.1 + pending_cell_htlc_fails.1);
 			assert!(commitment_update.update_fail_malformed_htlcs.is_empty());
@@ -3221,7 +3242,7 @@ pub fn reconnect_nodes<'a, 'b, 'c, 'd>(args: ReconnectArgs<'a, 'b, 'c, 'd>) {
 				node_b.node.handle_update_fail_htlc(&node_a.node.get_our_node_id(), &update_fail);
 			}
 
-			if pending_htlc_adds.1 != -1 { // We use -1 to denote a response commitment_signed
+			if !pending_responding_commitment_signed.1 {
 				commitment_signed_dance!(node_b, node_a, commitment_update.commitment_signed, false);
 			} else {
 				node_b.node.handle_commitment_signed(&node_a.node.get_our_node_id(), &commitment_update.commitment_signed);
@@ -3230,7 +3251,7 @@ pub fn reconnect_nodes<'a, 'b, 'c, 'd>(args: ReconnectArgs<'a, 'b, 'c, 'd>) {
 				// No commitment_signed so get_event_msg's assert(len == 1) passes
 				node_a.node.handle_revoke_and_ack(&node_b.node.get_our_node_id(), &bs_revoke_and_ack);
 				assert!(node_a.node.get_and_clear_pending_msg_events().is_empty());
-				check_added_monitors!(node_a, 1);
+				check_added_monitors!(node_a, if pending_responding_commitment_signed_dup_monitor.1 { 0 } else { 1 });
 			}
 		} else {
 			assert!(chan_msgs.2.is_none());
diff --git a/lightning/src/ln/functional_tests.rs b/lightning/src/ln/functional_tests.rs
index 0a685f534..c0e334326 100644
--- a/lightning/src/ln/functional_tests.rs
+++ b/lightning/src/ln/functional_tests.rs
@@ -17,7 +17,7 @@ use crate::chain::chaininterface::LowerBoundedFeeEstimator;
 use crate::chain::channelmonitor;
 use crate::chain::channelmonitor::{CLTV_CLAIM_BUFFER, LATENCY_GRACE_PERIOD_BLOCKS, ANTI_REORG_DELAY};
 use crate::chain::transaction::OutPoint;
-use crate::sign::{ChannelSigner, EcdsaChannelSigner, EntropySource, SignerProvider};
+use crate::sign::{EcdsaChannelSigner, EntropySource, SignerProvider};
 use crate::events::{Event, MessageSendEvent, MessageSendEventsProvider, PathFailure, PaymentPurpose, ClosureReason, HTLCDestination, PaymentFailureReason};
 use crate::ln::{ChannelId, PaymentPreimage, PaymentSecret, PaymentHash};
 use crate::ln::channel::{commitment_tx_base_weight, COMMITMENT_TX_WEIGHT_PER_HTLC, CONCURRENT_INBOUND_HTLC_FEE_BUFFER, FEE_SPIKE_BUFFER_FEE_INCREASE_MULTIPLE, MIN_AFFORDABLE_HTLC_COUNT, get_holder_selected_channel_reserve_satoshis, OutboundV1Channel, InboundV1Channel, COINBASE_MATURITY, ChannelPhase};
@@ -3880,13 +3880,13 @@ fn do_test_drop_messages_peer_disconnect(messages_delivered: u8, simulate_broken
 	} else if messages_delivered == 3 {
 		// nodes[0] still wants its RAA + commitment_signed
 		let mut reconnect_args = ReconnectArgs::new(&nodes[0], &nodes[1]);
-		reconnect_args.pending_htlc_adds.0 = -1;
+		reconnect_args.pending_responding_commitment_signed.0 = true;
 		reconnect_args.pending_raa.0 = true;
 		reconnect_nodes(reconnect_args);
 	} else if messages_delivered == 4 {
 		// nodes[0] still wants its commitment_signed
 		let mut reconnect_args = ReconnectArgs::new(&nodes[0], &nodes[1]);
-		reconnect_args.pending_htlc_adds.0 = -1;
+		reconnect_args.pending_responding_commitment_signed.0 = true;
 		reconnect_nodes(reconnect_args);
 	} else if messages_delivered == 5 {
 		// nodes[1] still wants its final RAA
@@ -4014,13 +4014,13 @@ fn do_test_drop_messages_peer_disconnect(messages_delivered: u8, simulate_broken
 	} else if messages_delivered == 2 {
 		// nodes[0] still wants its RAA + commitment_signed
 		let mut reconnect_args = ReconnectArgs::new(&nodes[0], &nodes[1]);
-		reconnect_args.pending_htlc_adds.1 = -1;
+		reconnect_args.pending_responding_commitment_signed.1 = true;
 		reconnect_args.pending_raa.1 = true;
 		reconnect_nodes(reconnect_args);
 	} else if messages_delivered == 3 {
 		// nodes[0] still wants its commitment_signed
 		let mut reconnect_args = ReconnectArgs::new(&nodes[0], &nodes[1]);
-		reconnect_args.pending_htlc_adds.1 = -1;
+		reconnect_args.pending_responding_commitment_signed.1 = true;
 		reconnect_nodes(reconnect_args);
 	} else if messages_delivered == 4 {
 		// nodes[1] still wants its final RAA
@@ -8777,7 +8777,8 @@ fn do_test_onchain_htlc_settlement_after_close(broadcast_alice: bool, go_onchain
 	assert_eq!(carol_updates.update_fulfill_htlcs.len(), 1);
 
 	nodes[1].node.handle_update_fulfill_htlc(&nodes[2].node.get_our_node_id(), &carol_updates.update_fulfill_htlcs[0]);
-	expect_payment_forwarded!(nodes[1], nodes[0], nodes[2], if go_onchain_before_fulfill || force_closing_node == 1 { None } else { Some(1000) }, false, false);
+	let went_onchain = go_onchain_before_fulfill || force_closing_node == 1;
+	expect_payment_forwarded!(nodes[1], nodes[0], nodes[2], if went_onchain { None } else { Some(1000) }, went_onchain, false);
 	// If Alice broadcasted but Bob doesn't know yet, here he prepares to tell her about the preimage.
 	if !go_onchain_before_fulfill && broadcast_alice {
 		let events = nodes[1].node.get_and_clear_pending_msg_events();
diff --git a/lightning/src/ln/payment_tests.rs b/lightning/src/ln/payment_tests.rs
index 440af3c9a..d88730c22 100644
--- a/lightning/src/ln/payment_tests.rs
+++ b/lightning/src/ln/payment_tests.rs
@@ -611,7 +611,7 @@ fn do_retry_with_no_persist(confirm_before_reload: bool) {
 	nodes[1].node.handle_update_fulfill_htlc(&nodes[2].node.get_our_node_id(), &htlc_fulfill_updates.update_fulfill_htlcs[0]);
 	check_added_monitors!(nodes[1], 1);
 	commitment_signed_dance!(nodes[1], nodes[2], htlc_fulfill_updates.commitment_signed, false);
-	expect_payment_forwarded!(nodes[1], nodes[0], nodes[2], None, false, false);
+	expect_payment_forwarded!(nodes[1], nodes[0], nodes[2], None, true, false);
 
 	if confirm_before_reload {
 		let best_block = nodes[0].blocks.lock().unwrap().last().unwrap().clone();
diff --git a/lightning/src/ln/shutdown_tests.rs b/lightning/src/ln/shutdown_tests.rs
index 846bcaf90..1310d25d4 100644
--- a/lightning/src/ln/shutdown_tests.rs
+++ b/lightning/src/ln/shutdown_tests.rs
@@ -209,7 +209,7 @@ fn test_lnd_bug_6039() {
 	let mut nodes = create_network(2, &node_cfgs, &node_chanmgrs);
 	let chan = create_announced_chan_between_nodes(&nodes, 0, 1);
 
-	let (payment_preimage, payment_hash, ..) = route_payment(&nodes[0], &[&nodes[1]], 100_000);
+	let (payment_preimage, ..) = route_payment(&nodes[0], &[&nodes[1]], 100_000);
 
 	nodes[0].node.close_channel(&chan.2, &nodes[1].node.get_our_node_id()).unwrap();
 	let node_0_shutdown = get_event_msg!(nodes[0], MessageSendEvent::SendShutdown, nodes[1].node.get_our_node_id());
diff --git a/lightning/src/util/test_utils.rs b/lightning/src/util/test_utils.rs
index 8e2be87d8..09c99815b 100644
--- a/lightning/src/util/test_utils.rs
+++ b/lightning/src/util/test_utils.rs
@@ -62,7 +62,6 @@ use regex;
 use crate::io;
 use crate::prelude::*;
 use core::cell::RefCell;
-use core::ops::Deref;
 use core::time::Duration;
 use crate::sync::{Mutex, Arc};
 use core::sync::atomic::{AtomicBool, AtomicUsize, Ordering};
@@ -297,6 +296,7 @@ pub(crate) struct WatchtowerPersister {
 }
 
 impl WatchtowerPersister {
+	#[cfg(test)]
 	pub(crate) fn new(destination_script: Script) -> Self {
 		WatchtowerPersister {
 			persister: TestPersister::new(),
@@ -306,6 +306,7 @@ impl WatchtowerPersister {
 		}
 	}
 
+	#[cfg(test)]
 	pub(crate) fn justice_tx(&self, funding_txo: OutPoint, commitment_txid: &Txid)
 	-> Option<Transaction> {
 		self.watchtower_state.lock().unwrap().get(&funding_txo).unwrap().get(commitment_txid).cloned()