Before you ask, I contacted the twitter team and they couldn't help.
Just got bit by the married segment rule. Booked SXM-CLT-STL last March for Jan 2023 because J seats were going fast (our preferred itinerary sold out in Feb!) Booked an overnight because the layover was 1:20 The I->D MCT is 1 hour, "so 1:20 is sufficient time to connect." But if we'd missed our flight because TSA was slow or baggage took a half-hour to arrive, since we had to go through Customs and Immigration and TSA, We'd be on our own for lodging at the last minute. I suppose there are rocking chairs in CLT. The layover went from 1:20 to 2:20 with the schedule change, so I tried to book the now-reasonable connection. No luck because they have to rebook the entire itinerary, and there's no availability on the SXM-CLT segment (of course not, we're in two of the seats already.) So, they moved us to the earliest flight the following day instead of the 11 am we'd originally booked so we could have a leisurely overnight. Can't change to a later flight because of married segments again.
Essentially, AA is saying, "You should have rolled the dice on connecting the same day because we think you can get through customs and re-clear security in 45 minutes (remember, doors shut 15 minutes early), and we're even giving you a whole 20 minutes more. Now, we've changed the schedule to be as inconvenient as possible for you, and we're not going to do anything to fix it."