The customers who were lucky enough to order the 40kwh version and who will get the 60 are blessed with luck. If they had got a real 40kwh battery then the degradation of the battery will all have been borne by you the customer from its first charge onwards. As it stands you will continue to enjoy a full and healthy 40kwh range for the duration of your ownership, because as the 60kwh battery degrades, it will be degrading from the 60 and Tesla motors is bearing the degradation there. It will be years and years before the degradation gets the battery down to a true 40kwh capacity. Imo you all should never upgrade since all you'll be doing is taking ownership of the degraded block of the battery so to speak. Enjoy the bonus battery life that you have been given and the better performance. You guys are the real winners!