Christmas and Thanksgiving are two of the worst times for travel, both weather and delays of all sorts. While Christmas day typically is not bad I would not chance that short of a connection time.
I would get on the phone with AA and go up the ladder if needed and try to get them to work with changing your flights. Not sure what options you have but I would be very nervous with your connection time.
If this change impacted your original flight time by an hour (I think) you should be able to change/cancel without any problem.
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