An airline wouldn't kick you out at, for example, 1499 hours if you need 1500 to get the ATPL. Reason being, it's in the airlines interest to keep you.
The reason why P2F schemes will boot you off is for the next load of people to P2F. Whereas you aren't P2F, you've been training for 18 months for this airline. Plus nobody would join another MPL with that airline if everyone got booted off before getting an ATPL.