Had the same issue with the 45 minute prior check-in. I heard of such a thing being 30 minutes prior to check-in due to security reasons, we were at the 35 minute point so they definetely said no. Their computers had already siezed up is what we were told, a security measure...federal rules to be exact. Funny cuz Allegiant does no such thing.
So we were stuck in Reno for the night and got the next flight out, said my buddies bag was to large for the over head compartment, yet it was fine on the arrival. So he had to pay. The couple in front of us had a bag that weighted 51 pounds, 1 pound over and gave them grief. The lady freaked out and started taking out shoes and clothes and shoving it in carry ons. I don't blame her, 1 pound over really? They don't know what customer satisfaction is, I'll stick with Southwest and Allegiant thanks !