阿拉斯加航空更改了里程的过期规则，现在开始不在过期了。然而阿拉斯加账户是会过期的，如果两年无里程活动，就会被 lock 进入 inactive 状态。你需要打电话验证身份，才能被 reactive，账户中的里程不过期。而如果你没有在一年之内 reactive，那么账户就会被清空，里程也会清空。所以说..其实就是过期时间是三年。。。
Do my miles expire?
Mileage Plan miles do not expireIf miles don’t expire, does that mean my account will remain active indefinitely?For account security purposes, we will continue to lock accounts that have been inactive for more than 2 years. If your account has been locked due to inactivity, call Guest Care to verify your identity, and they’ll reactivate the account for you. All miles in the account will still be there for you to use.
If a deactivated Mileage Plan account is not reactivated within 1 year after deactivation (3 years after your last qualifying activity) , it may not be reactivated in the future, and all Mileage Plan miles previously associated with that account will be forfeited.