Yes.

United has a 1 year (and 500 hour) minimum for upgrade. Several bids ago there were NB captain slots that went unfilled in junior bases. Put another way, anyone could upgrade with the minimum time. The "time to upgrade" was just a function of whoever was the most junior person to request it.

A couple bids ago those unfilled slots progressed to Chicago and Denver. On the most recent bid United awarded MANY more captain slots in Houston than they advertised because that was the only place left with eligible bidders. Nothing went unfilled in Houston but they awarded down to rough seniority level other bases saw with unfilled slots. It's very likely another bid will put the upgrade time right at minimums for all hubs.

There are also MANY more captains than FO's in IAH which should be interesting.