Bucket inventory is currently zeroed out, but I suspect they will open up seat availability in a few days as they rebook passengers who were on AA1910. Seat bucket availability currently being zero does not mean flight is necessarily fully booked in terms of passengers for every seat.
Bucket availability on AA2215 is zeroed out on a few other Saturdays right now as well -- 12/24, 12/31, 1/14, 2/11, and 3/11. AA1087 is zeroed out on a few of these days as well.
AA1910 was scheduled to operate on Saturdays from 12/17 to 03/11.