Yes, it is still available. The way it works is that the full $7,500 credit is available IN the quarter where #200,000 is reached, AND the next quarter after that. Since GM did NOT reach 200K last quarter, the earliest it could be reached is this quarter, and if it IS reached in Q4 2018, then buyers in Q4 2018 *and* Q1 2019 would be eligible for the tax credit. Heck, even if GM messed up and they reached 200K *last* quarter but mis-counted and later correct - Q4 2018 is still the full $7500 tax credit.
Note 1: that is based on current law. If congress changes the law, anything could happen. If they change it in 2019 for 2019 tax year and you bought in Q1 2019, you're screwed. Heck, if they change it Jan-Apr 2019 for *2018* tax year, you are screwed.
Note 2: it is a tax *credit*, not a rebate. If your total taxes for the 2018 tax year are less than $7500, you won't get the full $7500 you could get if your taxes were higher.
Note 3: If your total taxes for the year *are* less than $7500, maybe you can generate additional income before Dec 31. For example, by moving $$$ from a traditional IRA or 401(k) plan (deferred taxes - you deduct from income when you put in, but you pay when you take out) into a Roth IRA (no deduction when you put in, not taxes when you take out). Or, you could sell stock that would generate capital gains, and up your tax bill. You would have to figure out exactly how much to move/sell to kick your taxes up to somewhere around $7550, or $7600, so that you could your taxes would be JUST a teeny, weeny bit over the tax credit, so your taxes for the year would end up being $50, or $100, or some such (i.e., BIG rebate check from uncle sam).
Note 4: Your total tax for the year is COMPLETELY DIFFERENT from what you end up paying when you file your form, or the rebate you get. The latter two are based on your prepayments during the year, which are deducted from the total tax.
Note 5: Also, there is a tax credit you can take for installing an EVSE (what most people call a 'charger') - BUT it is very difficult to take it the same year you take the EV tax credit of $7500 (you'd end up in 'AMT' (Alternative Minimum Tax) range, and your credit would be disallowed. If you are buying the car in Nov, however, wait until Jan next year to install an EVSE (if you are going to install one anyways). That way, you *might* be able to get a credit for the 2019 tax year as well. You wouldn't get it for 2018 anyways (most likely) so you probably won't lose anything by waiting a month.
Note 6: Don't blindly believe me - go talk with a tax professional about all this. Edit: Note 3a:
If you generate additional income by moving $$$ from a traditional IRA or 401(k) plan into a Roth IRA : DO NOT get a check mailed to you in your name
. That is a *distribution* even if you deposit that check into a Roth IRA (OK, you can jump thru hoops and get it taken care of, but it can be a pain in the arse). You have the institution write a check to the Roth IRA (if it is a different institution) or just transfer it from one account to the other. That way it is a rollover, not a distribution. Distribution before you are 59 years 6 months old has loads of penalties. Talk to a professional about this
. If you already have a Roth IRA, then talk to them about what you need to do to make it a rollover - and get it in writing before you do it. If you don't have a Roth, talk to whoever manages your trad IRA or 401(k) about setting up a Roth with them, and what you need to do to make it a rollover.