JFOs are the pilots that upgraded out of the SO position. They are usually restricted to flights within the region so that they get a lot more takeoffs and landings than pilots on the long haul fleets. They also have tighter operation restrictions than a FO.

Right now I am hearing that it is approx 3 years to upgrade from SO to JFO (a little shorter on the A330 and a little longer on the B777). Then 2 years to FO and then approx. 8-10 total years with CX to passenger fleet captain, again depending on the fleet. Freighter captain is much faster...as low as 22 months as of late.

FO