I received an SMS last week telling me that from the 31st Oct 2011 to 27th Oct 2012, some AA flight numbers were changing. The flight numbers related to bookings I made for April next year which was fine, but we also have bookings for Nov this year, which I didn't receive any notice of. I phoned AA and when I eventually got through to talk with them, I found out that I needed new itinery's with the new flight numbers on them. I think that if I hadn't phoned them, they wouldn't have changed the flight numbers themselves and re-sent them automatically. Any others who receive the same messages & emails would be advised to contact AA to get there itinery's changed or the original one's might not be accepted at the airports.