When will AA pull their retired aircraft out of the schedule?
Probably bit by bit. Airlines are only updating schedules a few weeks to a month at a time right now, and much closer in than usual. It's been mentioned a lot recently that airlines stand to benefit from cutting schedules as close in as possible in order to minimize refund costs.
How does that minimize refund costs? I am curious to know. It is a genuine question, not being sarcastic.
My guess is CASH FLOW and BORROWING COST. If you cancel too far away, a lot of refund request will flood in and in a few days you have to refund for months and months of tickets, that is a lot of money going out in the short time. But if you cancel by week at a time, you can manage the CASH FLOW in a much slower pace. So instead of refunding $300million in the day you announce a month worth of cancellation, you only refund $70million each week (above figures are for illustrating only, not actual).
Also, a big spike in reduced cash reserve is not a good thing, and that may increase your debt interests as the investor gets panic. A managed flow out in cash reserve (although the final amount might be the same), could calm down the investors (bond ad debt) in theory. Thus keep the borrowing cost low.