The promotion requirements will be in the baby operation manual and approved by the CAA, even if they are running on the mainline AOC.
As for low hours we all have to start somewhere. I was fortunate enough to secure a job as a first officer on the Viscount at the age of 20 with just 165 hours total time. BEA used to put "hampsters" straight onto the Trident and BOAC onto the 707 and VC10.
MP
