diff --git a/doc/FAQ.md b/doc/FAQ.md
index f5279cf37..3618a0639 100644
--- a/doc/FAQ.md
+++ b/doc/FAQ.md
@@ -73,7 +73,8 @@ There is no risk to your channels if your IP address changes.
 Other nodes might not be able to connect to you, but your node can still connect to them.
 But Core Lightning also has an integrated IPv4/6 address discovery mechanism.
 If your node detects an new public address, it will update its announcement.
-For this to work binhind a NAT router you need to forward the TCP port 9735 to your node.
+For this to work binhind a NAT router you need to forward the default TCP port 9735 to your node.
+IP discovery is only active if no other addresses are announced.
 
 Alternatively, you can [setup a TOR hidden service](TOR.md) for your node that
 will also work well behind NAT firewalls.
diff --git a/doc/TOR.md b/doc/TOR.md
index db09762c3..af5efb016 100644
--- a/doc/TOR.md
+++ b/doc/TOR.md
@@ -48,8 +48,9 @@ network between you and the Internet, as long as you can use Tor you can
 be connected to.
 
 Note: Core Lightning also support IPv4/6 address discovery behind NAT routers.
-For this to work you need to forward the TCP port 9735 to your node.
+For this to work you need to forward the default TCP port 9735 to your node.
 In this case you don't need TOR to punch through your firewall.
+IP discovery is only active if no other addresses are announced.
 This usually has the benefit of quicker and more stable connections but does not
 offer additional privacy.
 
diff --git a/doc/lightningd-config.5.md b/doc/lightningd-config.5.md
index 20c0d7b79..433c38018 100644
--- a/doc/lightningd-config.5.md
+++ b/doc/lightningd-config.5.md
@@ -380,7 +380,8 @@ as described below).
 
 Core Lightning also support IPv4/6 address discovery behind NAT routers.
 If your node detects an new public address, it will update its announcement.
-For this to work you need to forward the TCP port 9735 to your node.
+For this to work you need to forward the default TCP port 9735 to your node.
+IP discovery is only active if no other addresses are announced.
 
 You can instead use *addr* to override this (eg. to change the port), or
 precisely control where to bind and what to announce with the