The current upgrade line is 13 years. It will probably go up to 15 and then drop to under 10. NetJets didn’t hire between August of 2008 and January of 2015. The retirements will pick up over the next decade. Also ask yourself why to people hang out in the right seat for 13 years? Why don’t they move on to the regionals for a quick upgrade or go to a ULCC?

Just like everything in aviation, it’s all about timing.