As has been mentioned, you'd need to see an Engineering Change Order and the maintenance log for the aircraft to determine when it was carried out. Subsequent correspondence from AA would seem to confirm that they were still in use at that time.
The main issue was whether the document had been altered, and another person had suggested that, based on their industry / corporate knowledge, the revision numbers / dates did not match (see
here for detail). A List of Effective Pages or similar would probably be able to determine that, but we haven't been able to source one as yet.
Thanks for your replies.