@Plantwebguy and others seeing this thread,
Please check out the thread below and see if your symptoms match. We’ve been having trouble with switches, particularly and any action that requires cloud processing (local processing still works, which makes it look sporadic). You can do a search in the forums to find out how to tell if your action requires the could or not, but anything between your Phone App and the Hub is cloud based.
ST denies a widespread outage and says its just a few of us. In our thread, we’re now up to about 15 users who have non-responsive hubs and have been cold (no Thermostats!!!) and dead since early December.
Please take a look at this thread and add yourself to the TWO tickets that are tracking these problems if your symptoms match. Thanks!