Update: I was also getting the "increased battery discharge" message. I figured out it was one of the Comfort access door handles (it had been acting wonky for a few weeks). I disconnected the handle from the system and it took 2 or 3 days before I stopped getting the message. An interesting side affect was the A/C blower would run at reduced speed until the battery/charging system reached a certain threshold (I assume). It would run on high only in defrost.

All works great, CA, A/C etc.

FWIW, the BMWhat app showed no codes at anytime and charging voltage was anywhere from 13.1 -14.6v.