IMO we’ve planted the flag in BOS (finally!) and we should just open both. There is clearly more than enough flying in both fleets to cover it. The irrelevant “too close” (“mission” lol) nonsense means nothing. If the flying is there for each airframe, and it is, then bases make sense. JB has robust multi plane bases in NYC and BOS, in FLL and MCO. AK has multiple west coast bases close together. SWA has LA and LAS and PHX plus DAL and HOU. Covering trips with originating crews isn’t the same as projecting air power in a region.

The biggest factor preventing more bases IMO has been to preserve marketing’s ability to rapidly shift almost identical airframes on a dime for tiny upstream or downstream logistical savings. As both fleets continue to grow, that flexibility begins to exist only on the margins and not in the bulk of the flying.

While new categories can drive training churn initially, more base choices tends to stabilize and probably reduce training in the long run, as there is less incentive to chase things when more pilots are “locals”. And the company has clearly figured out how to minimize that initial churn anyway.

It doesn’t have to be either/or. There is clearly more than enough flying for both there. So the only reasons to open or not open NB bases there would be hotel costs and, more importantly, origination crew reliability vs panicked RR shuffling.