It's pretty obvious what is going on here, and I doubt that Elon is not clued in, especially given McNeil's bonus plan. I expect a major upgrade to the interior for the S & X to be announced and available the first week of October. That means all of the existing inventory cars would have to be discounted at that time because of no longer being the latest/greatest. Instead, Tesla is discounting them now to drive Q3 sales. In Q4 they will have the spiffy new interior as a draw and discounts won't be necessary, except for any leftover old interior cars. So with this upgrade Tesla is able to generate additional demand in both Q3 and Q4 - precisely what they need to do in order to have 2H17 deliveries exceed 1H17 deliveries as they guided a month ago.