Tesla Motors Club

I have a model 3 that’s about 14 months old and a little over 12,000 miles on it. A couple months ago I had to have the BCM replaced which took almost 2 months of waiting for the part to come in before replaced. During those two months of waiting, I had some serious phantom draining while the car sat in my garage. I was averaging a loss of 30+ miles a day when typically it’s only 3 miles a day. Yesterday when I opened the door to the car, It started to glitch out and eventually shutting down all power to vehicle. The lights were flickering and the center screen looked like something out of the matrix. I received the message that my 12v battery needed to be replaced. I tested the battery and it read 100% charge with a voltage over 13v. I managed to reset the code by disconnecting the battery under the frunk and also the battery under the backseat. After that the car was running correctly, but this morning I see that the message has reappeared. My question is, could the battery have been damaged during those two months of phantom draining before the BCM was replaced or is there another known problem that could be happening? I love the car, but the issues I’ve been running into in a short amount of time and the fear of being stranded somewhere are starting to outweigh the love.