It appears that since the break with Delta, AS has been regularly closing the lounge to non-Club members. When it was partners with DL, we never had any trouble accessing it on arrival or departure.

There are legendary tales of guys with Club membership who worked at the airport or nearby, in years long past, convening in the Club (then called the Board Room) for pancake breakfasts with no boarding passes required. There was an abrupt stop put to such when Alaska became aware of it.