Did you ever figure out a way to make a phone with Android 12 work with the app? My JK BMS was working fine, and now that my phone is upgraded to android 12 it won't even see the BMS in the JK BMS app. In bluetooth it sees it, but won't connect since it is only designed to connect via the app. I would prefer not to revert my phone back to android 11...
What version of the app are you using? I think 4.6.1 is the latest.