For my fork https://github.com/neilh10/ModularSensors/releases/tag/v0.30.0.release1_211023
I got the WiFi S6 communicating reliably, and its been testing for over a couple of weeks.
It seems on going to sleep, it really wasn’t doing what was necessary to be able to sleep. It seemed to be leaving TCP/IP links setup. Which then depending on network timers, might be there when it wakes up. If the sleep time was short enough it would still have the link available. Since it used to work, probably what happened was a timer somewhere else (MMW) was reduced. The cure in the end was on sleep, change the destination IP to local:, and then sw reset the device. Then when it wakes up, it reconnects to the SSID, and then setups up the TCP/IP to the remote MMW.
https://github.com/EnviroDIY/ModularSensors/issues/347 describes the issue