Just found a bug with the watch dog timer that is present in v6.38 at least.
Set a watch dog timer to ping an address, say 126.96.36.199. Tick enable watchdog timer.
So far this works as intended.
However if you go back and untick watchdog timer, it still resets if it's unable to ping 188.8.131.52.
You have to remove the IP as well to get it to stop resetting.