I was reading up via the WSD-1503CPH.pdf for other reasons, then something hit me. You don't suppose this can happen when meat is fairly cold and controller gets a in-accurate reading that is trips up on? I haven't seen this yet myself, but maybe the lower temps cause strange things to occur. Adding an initial Time step seems like a good bet if this is indeed the case. Hopefully no one sees this later in the process / steps...
Pulled from the manual:
"e) Operating the controller when ambient temperature is below 32 °F (0 °C). The
controller reading is only accurate for temperature ≥ 32 °F (0 °C). In addition, if the
ambient temperature is below 14 °F (-10 °C), the controller will not function because it
can’t read the temperature correctly. In that case, user can warm the sensor by holding it
with their hands. Once the sensor is above 14 °F (-10 °C), it will turn on the heater. Once
the inside of the smoker is heated to above 32 °F, the controller will run by itself."