Yes, this release confirms that you must not set the NFA flag for that account. NFA compliance happens behind your back and your account behaves like a non NFA account.

Closing trades goes against the FIFO compliance, that's why it's forbidden by the NFA rules. But this is worked around in all broker platforms that I know, and only relevant when you directly trade with the broker API. The attempt to close a trade will then produce an error message.