as a related observation regarding disconnects (for whatever reason - in the following case neither suspend mode or an interrupted internet connection):
Yesterday I had devtools open to have a look at the tavern status traffic [obviously only XHR, since chat seems to default to flashsocket*, which can't be tracked that easily. And (nearly?) all live update messages are being sent over the chat connection, can be observed in the rare cases chat falls back to XHR-polling]
I noticed the FriendsTavernService packets dropping in from time to time (the chair icons updating accordingly), and after ~25 minutes of just watching, the updates stopped (no more packets, no errors) - and the chair icons remained in their last state, no more live updates (checked about an hour later all taverns manually, there were a lot with a 'free' sign which were full when entering, and also many vice versa).
I could perform all actions in the game, had a working global chat & got new mail notifications, but the tavern icons didn't resync anymore.
After a reload, updates were back & live again...
But since there is no 'Sync lost' warning, the only 'safe' way is to reload the game on a regular basis to make sure all server communication channels are working (seem to be independent; chat & tavern sign working, but no tavern icons in the example above; chat working [after that regular chat disconnect-reconnect], but new mails not flashing anymore; or the initial problem of the tavern sign being wrong while everything else [seemed] to work...)
/edit: * would be great if chat could use a transparent protocol here on beta, it would make such nasty bug hunting a lot easier...
/edit2: Observed the traffic a bit more - came to the conclusion that the [XHR] messages for updating a tavern's state only appear when the respective cooldown ends; that explains why those appear so rarely; so the state switching messages mainly arrive on the chat connection, which makes it hard again to investigate..