American Airlines CEO has officially stated that the airline is closely examining the need to have an order of 22 Airbus A350-900s incorporated into its fleet which it inherited after merging with US Airways whom had a fleet of 24 A330s which the A359s were destined to directly replace.
With a large fleet of Boeing 777s and B787s already in service, AA feels having a small sub fleet of A350s puts extra pressure on the entire system especially rotating them across its different hubs in USA.
In my view, there are two options here for AA to choose from:
1. Exchange 22 A359s for 44 A321NEOs
2. Exchange 22 A359s for 25 A330-900NEOs
Both options mentioned above are good and have their own respective pros and cons. The safe bet would probably be option 1 as it can also opt for many A321neoLRs and base them out of MIA for medium demand LATAM routes where using a 763 isn't viable plus to fly PHL/BOS to U.K./Ireland year round and in the premium config boosting frequencies to LAX/SFO from these two markets along with MIA.
Option 1 allows mega cost savings over the long run as its wide body fleet would exclusively revolve around the B777 and B787 families.
If Option 2 gets implemented, then AA should just base the aircraft out of MIA airport and use them on high demand flights year round to Europe and Latin America.