From the AS website:

Check in with bags: For flights between 6:00 - 11:00 a.m. arrive 3 hours prior to scheduled departure.

Check in without bags: 90 minutes prior to scheduled departure

Reservations are subject to cancellation if the passenger fails to be checked in and available for boarding at least 30 minutes before scheduled departure time (from the Contract of Carriage).

Sorry you lucked out. AS is usually a very good airline, but, like others can sometimes be overwelmed logistically.