I am seeing the same problem. A device on site occasionally loses all connectivity if site’s WiFi is interrupted, and it can only be solved by a device reboot. It’s revision:
Raspberry Pi 3, Resin OS 2.0.3+rev1 (prod), supervisor 4.2.2
The device is mounted inside a tamper-proof box, many miles away, so I’m not going to be able to debug it directly.
Is there a way of forcing the device to automatically do a full hardware reboot if it loses connectivity for more than a given period of time (e.g., a few hours). It’s not an ideal solution but at least it means if I do lose my connection to it I can rely on knowing I’ll get it back within a few hours.