I certainly don't know the regulations of ETOPS. But when SCA flies to London they have scheduled fuel stops in ( I think ) New Brunswick, Canada. So does this influence the crew issue? I guess it would if they have a crew that layovers in N.B. and they swap. I would bet the 737 doesn't have bunks but I do know of some airlines that positive space a first class seat for "crew rest". My assumptions as well. Maybe someone will chime in.

It would certainly be nice to know if they type rate their FOs at time of hire. But I am just not about to ask that question in an interview.