[Tzfat]

ETOPS is listed on the flight release as Special Equipment.

That means that it may not have even been the flight crew that messed up. It might have been as simple as the special equipment list being incorrectly registered in the database for ETOPS. That would explain how Aircraft Routing, Dispatch, Maintenance, and Flight Ops all missed the fact that that nose number was not certified.

All AA’s A321s are configured the same in systems. Even those that are not certified ETOPS must maintain ETOPS APU checks etc. It is only a paperwork differentiation.

[BatGuano]

In the end AA gets fined and, hopefully, we all learn from the mistake. I retired 15 years ago and flew ETOPS from the early 90’s to 2000. Mostly to and from Europe. Before entering the North Atlantic tracks, we had to send an “E OK” message to dispatch. All involved knew what animal we had strapped on.
Flew the B-777 shortly after it came out and it was certified for 180 minutes “off the shelf.” No ETOPS to Hawaii yet back then. I flew the 737 back when we thought that Knoxville to New York was too long!