Ours did the exact same thing on Sunday evening (12/26/2021). I qued the iPad OS 15.2 update for all units, and sent the command. Almost instantly I noticed all my clients were offline. I would be willing to bet the clients were actually down prior to sending the command to perform the update. Most of my clients were back online yesterday (12/27/2021) by around 1200, and today everything seems to be working normally.  ... View more