Ah yes, your right, USA only! So that is good news for all of 2017 for sure. The IRS reads:
The new qualified plug-in electric drive motor vehicle credit phases out for a manufacturer’s vehicles over the one-year period beginning with the second calendar quarter after the calendar quarter in which at least 200,000 qualifying vehicles manufactured by that manufacturer have been sold for use in the United States.
So it really depends on what 2017 looks like for MS/MX in full for Model 3 in 2018. Cool.
so the magic dates are 7/1/2017, 10/1/2017, 1/1/2018, 4/1/2018 (etc?)(beginning of calendar quarters) whenever they hit 200,000 (unless rules get upgraded after the 2016 elections)
{seriously considering an S85 CPO or similar}