Received this today from an ex-colleague:
Blurb to AA staff:
Dear Airport Agents, Premium Services Representatives and Reservations Representatives,
[...]
As you know, we’ve been very focused on ensuring that we have strong service recovery programs in place to help during those times when the weather isn’t on our side or when other disruptions to our operation occur. One tool that we use to help get customers back on their way during irregular operations are the interline agreements we have with various carriers that allow us to reaccommodate passengers on other airlines at a negotiated rate.
These agreements also allow airlines to book, sell, ticket, and check baggage on one another. Interline agreements are common across the industry and they generally include a standard, discounted rate for calculating how much is owed by one carrier to another to use their seats during irregular operations.
In April of this year, participating airlines across the industry agreed to new rates for moving customers between carriers during irregular operations. Delta recently decided to go outside of that joint agreement and negotiate an individual agreement with American. We have been unable to come to terms on an agreement with Delta and, as a result, have mutually agreed to end our interline agreement effective September 15. From that date, neither airline will offer interline services to each other, including the ability to rebook passengers at discounted rates on the other carrier when flight disruptions occur. (Note that we will continue to honor valid tickets already purchased on or before September 14 through the existing interline agreement, so there will be no changes there.)
While this is a change, it will not affect our commitment to reaccommodate customers during irregular operations. The new American now has the world’s largest and best network and our team is doing a great job of running a reliable airline. With nine hubs and gateways and nearly 7,000 daily flights, we have more ability to re-route our customers during operational disruption than any other airline in the world. We also have options with our joint business and oneworld partners, plus we have an interline agreement with United, which has the second largest network, and many other airlines, such as Alaska Airlines.
[...]
If I'm not mistaken this the first interline agreement cancellation by major legacy airlines. One will no longer be able to buy an AA, or DL, ticket for travel including the other airline.
Inevitable, I suppose, but a loss for consumers.