The standard lock is two years. If you can’t hold the aircraft you are on in the base you want, for seniority reason or if the aircraft isn’t in the desired base, you can be awarded an aircraft in the base you want after one year. You would just carry your remaining seat lock and add it to the new 2 year lock.

Crazy part is, if the recent past stays the same, a DTW 717 who wants New York could take an upgrade and potentially move sooner than one year since an initial A bid is not blocked by a seat lock.