Did you find a solution for this particular issue?
I have the exact same error (Server error: UID MOVE: IMAP session state is inconsistent, please relogin.
) when I try to delete messages in a particular email account with Roundcube. I've also tried to delete the messages with Horde, but it shows another error: An error occurred while moving messages from "Inbox" to "Trash". This is what the server said: The IMAP server closed the connection. IMAP error reported by the server
It happens in a specific email account within the same cPanel user.
The only difference I've managed to find between that email account and the rest (from the same cPanel user) is that in that account, the storage used is way higher than the average Joe. About 15 GB. For the rest, everything seems to be exactly the same.
If you have any news, please let me know. I've checked online all the way around and haven't found anything useful so far.