<Finally got to look at the rule> ... Yup, I see no wiggle room at all. Even if you had a Boeing type rating on your FAA commercial certificate, you'd still have to take the training (in a specific approved program) to take the written after August 1st. People have been saying that there will have to be some rule modifications - and I agree - but don't hold your breath.
eCFR ? Code of Federal Regulations