This is how you game the EV credit system: (from SA comments)
"I wrote months ago if I was running Tesla with where I believe they are in hitting 200k U.S. sales, I would be pumping up production in hopes of catching as many sales as possible after hitting 200K shortly after July 1."
Indeed. Tesla is delaying Model S/X US sales, doing as much international sales as possible in Q2 to reach 200k mark in July. This also help to make Q3 as best as possible.
So, we are looking at full FTC for all of 2018, half of it ($3750) in Q1-Q2 2019, and a quarter of it ($1875) in Q3-Q4 2019. Anyway, this is the first step that is important. A boost in sales in Q4 will be followed by a plunge in sales in Q1 in the US."