I have the same problem. Started today. All devices say they are connected to the network but they cannot be controlled via the network. I did get sporadic connection to two timers though but that’s now gone.
It was fine for the past week since I installed. There was an App update today. Coincidence?
I deregistered one timer but can’t get it to reconnect even via Bluetooth, despite phone and timer being in pairing mode. It doesn’t see the network either. Rebooted hub and router.