Is there an issue on Plex's end? Remote access is offline, but server indicates fully accessible.

Plex server version 1.13.0.5023
Configured for remote access.
pfSense firewall has inbound NAT configured for access to Plex server on 32400.

Remote access setting indicates Fully accessible outside your network.
Green checkmark.

Locally, I can browse to server and view/listen to content.

Remotely, server is offline using the following.
Android app version 6.17.0.4824 - ‘offline’
https://app.plex.tv/desktop - ‘The server “SERVERNAME” is unavailable’

I can also browse directly, remotely to the server, login and view/listen to content. This at least confirms the remote access through my firewall is working as expected.

Further supports issue may be on Plex’s side, as the Android app and app.plex.tv are still failing.

NEVERMIND. Looks like an app update re-disabled “Allow insecure connections”.
Set it to allow insecure, can connect to server again.

A problem has just been identified caused by recent migrations of pubsub Plex.tv servers - it is being looked into And changes have been made to stop the behaviour seen here : remote access status showing unavailable but is actually working