I'm pretty certain they are going to deliver the 200000the car on Sunday or Monday.
They know EXACTLY how many cars have been registered and they know exactly how many are GOING to be registered on a daily basis. So, they CAN time this exactly if they want to.
There would be NO REASON to stockpile cars like they have been doing throughout end of May and all of June 2018 if they weren't trying to do one of two things, or both.
A) get the 200kth car into Q3 in order to totally maximize the 7500$ for new buyers for the period in their history where they will sell many MULTIPLES of cars more than they ever did in the past.
B) goose Q3 revenues for stock manipulation purposes, so all those orders working through the production snake stomach all pop out in Q3.
C) both of the above.
re: B), I don't really think they would do this from a corporate accounting standpoint. Elon has already commented that they will be "cash flow" profitable in Q3/Q4, so the market isn't going to be surprised when the achieve that.
So, the answer is A!