After 4 months and 12k miles, my battery suddenly lost about 4% capacity. Interesting that it happened just after the last Tesla Corsa event.
I called Tesla about it and asked if my car was subject to the TSB battery issue with improper connections of the cells. They said that it is not.
90% charge is now 268, and 100% is now 299 miles. I tried charging to 100% to see if it would recover but it didn't. Other users reported that they slowly regained mileage as the battery balanced near 100%, often taking an hour to get the last few miles. Mine at 297 said 1 hour 10 minutes to charge, and was still charging at a decent rate. When it hit 299 it abruptly stopped charging.
I guess I am within the 5% in the first year, but I didn't expect the whole range loss to happen in 1 weekend, thought it would be slowly lost. Granted I drove the car harder than it had ever been driven, maybe that had some effect.