I've been shopping for a Model S over the last month or two and routinely spec out cars on the website. As part of that build process, once the options/colors/wheels/interior are all selected, I have been clicking the red "next" icon in order to see what the delivery date options are and to put in deposit information. Up until today, changing the month of delivery was always an option. For example, in the last couple weeks Late August, September, or October were all choices that could be made. However, when I logged on this evening I noticed that the option to take delivery in a certain month is now gone. All it says is "Late September Delivery" at the bottom of the cost calculator on the "Build your tesla" page. It appears that if an order is placed today that only a September delivery date is possible. This got me thinking about reasons why they would change it, and I have a couple thoughts as possibilities. 1. They are forcing people to take delivery before the end of Q3 in order to boost quarterly deliveries. 2. There is an update to some key part of the car (the interior?) that will preclude cars that are ordered now from being built later than September. If Tesla plans to make a change to the manufacturing line so that 100% of the cars from that point will be updated, then cars ordered today could not be built after the manufacturing change is made. Tesla would not want to build cars in September and then hold onto them for another month or two for deliver, so they have just taken away that option. Maybe this new update is the other reveal at the Tesla Semi event? Thoughts?