As far as I can tell on the bid, it appears that the Q upgrade classes are not filling, i.e. street captains are still a "thing." The E175, however, is currently around the 2.5 year seniority mark. These things have fluctuated a ton in the last couple of years.

So by the time you read this, apply, interview, get a CJO, report to the schoolhouse, pass the sims, complete OE and hit the line, there's one thing you can bank on - the time frame will change.