I think this is a really interesting discussion. There is evidence and logical conjecture to support both sides of the argument (old lights forever vs new lights any day now). I personally think the new lights are coming because it seems more Tesla-like, but the cost and US only arguments are strong. At the end of the day, Tesla themselves may not know. They may make a final decision on a Monday and then on Tuesday they change their mind. Maybe they have a plan, and then Elon tweets and everyone scrambles to change that plan.