So my defaults in the spreadsheet are pretty optimistic, yet realistic I think. But in the interest of fairness lets look at a less than desirable, yet realistic scenario too.

Go to my spreadsheet and type in:

100 Planes. (imagining after the 175s arrive, no more growth)

9 pilots per plane (imagining they decide to run as lean as possible)

2 per month attrition (imagining the whole industry slows)

And you'll see that you must push the projection out 4 years before the most senior guys in class right now will see an upgrade.