It's a very disappointing development. I'm not a fan at all of DL, but I fly in and out of ATL quite a bit. When AA has IRROPS involving ATL, AA options or AA alternate routings have always seemed to be unavailable or a huge problem to utilize.

So, I've been put on DL by AA a number of times to keep me from getting stuck overnight. It's not good news at all that this option is going away.

If my current itinerary structure stays the same next year, I may have to reconsider my carrier choices.