I have a 2020 3401 and only 2 air conditioners, but I don't have the option in the iN-Command system of gas or electric RV (furnace) heat.
From this forum, it appears the living room thermostat operates the propane furnace which heats all the floor ducts so that is for the living room, bathroom, bedroom and basement storage (including the small duct to the tanks in the underbelly).
The bedroom thermostat operates the electric heat pump heater in the Bedroom roof AC. I haven't confirmed, but there are numerous reports here that the heat pump wont actually work as an electric heater at outside temperatures of below 40-45oF.
To complicate things, Airexcel seems to indicate that the thermostat may be able to switch to propane furnace mode if the roof AC electric heat cant keep up ("Strike") in the attached document from their website https://www.airxcel.com/DesktopModul...t_function.pdf
I think this might be what XCMARK is referring to.
I do have the iN-Command option of electric or propane (or both) on my water heater. Note that there is an electric toggle switch on the water heater which needs to be 'on' in order for the iN-Command electric option for the water heater to work.