The reason I was wondering about the bluetooth dongle/firmware, is that that appears to be something you are doing differently from most with the overland solar controller. How are you using both the bluetooth dongle and the display?
I am also curious what is on the load terminals? You have to be a little careful with these as they are only able to carry current in one direction - if these were miswired where they could have charge flowing into the controller, it would be a problem.
Since there is only one plug on the MPPT for either the dongle of the MPPT control display I generally leave the dongle in all the time but plug in the MPPT control when I suspect the controller has failed. I bought the dongle to better monitor my solar system and try to become an informed user. I had intended to switch to the MPPT control when using the camper to avoid unnecessary RF but haven’t yet felt like I am the informed user I imagined myself becoming.
AS for what the load terminals are connected to I don’t know for certain. So little room to move around and check and no wiring diagram. Any easy way to figure this out?