NATS is a higher qualification. That requires a 2 flight CKA checkout.
Hawaii is lower and doesn't require a specific checkout.
Maybe I'm misunderstanding but doesn't Hawaii involve ETOPS training which many domestic pilots wouldn't already have?
I can see where a NATS ETOPS course and check out would be good for Hawaii and the NOPAC at many carriers.
So the FAA approved program means you could do a MIA-SJU flight and you're now qualified into C. America, S. America(not mountain cities which are individual special qualification airports), the Caribbean and Hawaii.
Is MIA-SJU operated under a '75 minute benign area of operation' rule? Sorta like regular ETOPS but you don't need a special signoff on the return leg and you get MEL relief for the 'ER' required items?