The majority of pilots at SkyWest don't take the first available upgrade.

Most junior captain at SkyWest just went to a March 07 DOH. Less than a year. About #2400 out of 2800+ on the seniority list. However, some 900 FO's senior to him decided they didn't want it or didn't meet the upgrade minimums. We've still got hundreds of FO's with 3-4+ years seniority that could, but haven't upgraded because they don't want to go to a junior domicle, or sit reserve in a senior one.

A misconception about regional flying (at least at SkyWest) is that everybody is chasing the quickest upgrade for the PIC time.