There have been various "flow throughs" over the years. There was a time when you got a CAL number when hired at Express, then the flow-through of 97-2001, then the "list" guys (almost flowed, but 9/11 changed the agreement), then the PIGS, etc. I think 400 pilots are from the last official 97-01 flow through. I've flown with CAL captains that were my Captains on the ATR at Express.