You are right that you are already on the most recent version of the firmware. Do you know how long the issue occurs after each reboot? On the microcontroller-based OpenSprinkler, there is a feature that reboots the controller when the last successful weather call is more than a day old. This is not implemented for OSPi, partly because RPi will manage the network connection, partly because rebooting RPi is a lot more disruptive than rebooting a microcontroller. Knowing the patterns of the issue (like how long does it take to occur and so on) will help us find way to diagnose.