I believe they’ve stated 4%ish growth /year. 4% of 17,000 is just shy of 700 pilots. Add in 400 or so retirements and you get to the 1,100 number they’ve stated they’d like to hire in 2024.

So we’ll say for arguments sake that we’re roughly 18,000 pilots by the end of 2024. Add roughly another 700 (assuming 4% growth) plus retirements and you’re starting to get close to 19,000. Extrapolate that out over a couple more years and we could (emphasis on could) be at about 20,000 pilots by 2028.