Not sure what you mean by "still in order"... You mean working? The mail shows OK...
I've run the "reconstruct -r -f" and it hasn't changed the behavior.
The "seen" status still doesn't sync correctly, and it appears I either have to restart imapd or the client for this to refresh to correct state.
I created a fresh profile in Thunderbird just in case, but this acts the same - the if I "read" the message, and it marks read in the client, then refresh the mail the status goes back to unread. It's like the server and thunderbird won't sync until either is restarted.