The airlines merged in 2013, but the flight-attendant management systems did not. The two systems could not intermingle, and flight attendants could only be assigned to planes associated with their respective legacy airlines... ...The lack of integration between the two systems also restricted flight attendants from applying for transfers to other hubs.

Now that the systems are fully integrated, the airline has greater flexibility but also a staffing imbalance. LAX and Dallas-Fort Worth International Airport each needs 700 more flight attendants, while Phoenix needs 700 fewer. With 13 airports where American can base flight attendants, it can deploy flight crews more efficiently if some employees are transferred out of Phoenix.

Wednesday morning, the airline notified Phoenix-based flight attendants to watch vacancies at other bases and consider opportunities to transfer. The airline hopes to naturally reduce the number of Phoenix staff over the next few years through attrition and transfers.

(As to the Phoenix hub) Vasu Raja, the airline's vice president of network and schedule planning, echoed Schubert in an emailed statement: “We remain committed to keeping the Valley of the Sun connected to the world. We recognize the unique value of Phoenix as a hub for American Airlines. More than 250 daily flights are important to our team members, customers and our business. We are here to stay."

American Airlines has 27,000 flight attendants distributed across 13 airports. Sky Harbor is home to 2,360 of those flight attendants.