I agree, GGU reissue after cancel is an area where AS is confusing with its messaging.
They now only seem to let Customer Care do it. I was told that it IS standard policy to reissue them when asked in the case of a cancellation, although the stern messaging is in place on the website basically just to warn you that they will not automatically re-deposit. Which makes no sense -- but of course, this is Alaska IT we're talking about.
(Agree that the reissue of a 2018 expiring GGU in 2019 would not be SOP and would indeed be an exception)