Recently purchased over the air 70 to 75 battery upgrade for my 1 year old Model s. Expected increase was 15 miles but actually got 6 miles. Talked to support and they ran diagnostics etc but they said that's all my car will get. 15 is just an estimation and given the car is 1 year old and got 23K miles it's not going to get any more than what it had got which is 6 miles. If tesla had told that it was going to get mere 6 miles I would not have wasted my $ and time. Sorry but its a ripoff!!