LOA 13 said that the NEA automatically renews in 5 years unless the metrics ARE NOT met. Even if they are not met, ALPA still needs to convince the company to exit the NEA. Absolutely toothless and unenforceable.

LOA 17 says that the NEA automatically terminates in 5 years unless the matrices ARE met. If they are not met, ALPA has to consent to allow the NEA to continue. (AIP B.3). It has much more tooth, but probably still unenforceable.