I recently bought a CPO 2013 Tesla Model S P85+ and every time I start the car in morning the brake pedal is super stiff, like a rock, and then it lets up to regular brake pressure. This only happens when I leave it overnight. I brought the car into the service center and they replaced the brake booster but this did not resolve the problem. I brought it in a second time and they are now telling me this is "normal" for my model year. I drove 4 Tesla loaners for a total of 4 months prior to this and none of them did this. Has anyone else experienced this? Is there some sort of leak in a brake system that is causing it to lose pressure overnight? Thanks!