As you know from the other thread, but for those who were not following the T6 power thread.
I recently found I could have the Hub notified of AC power loss by my Honeywell T6 Thermostat(s).
See this thread.
I would guess there is a chance any battery backed up thermostat could do the same.
In any case I plan on using it to shutdown my hub after an hour or so of no mains power.
