Just reading this thread reminds of the vexation felt as I tried to find the magic formula. Unfortunately the CAP509 course provides you with the basic qualification to get an airline job. However, the market dictates the current minimum requirements.
What makes it so frustrating is that the goalposts are liable to move. This is something that will happen throughout your career. First you need to get a job, usually on a turboprop, but you need 1000 hours, then you try to move to a jet, but you need 500 jet (type rating prefered), then you need wide body experience to go longhaul,and so it goes on until you get all of the aforementioned, by then of course you are too old to get any job. C'est la vie.
Anyway, the figures quoted by the schools include all those sponsored by an airline so it tends to give an optimistic picture.
However, since I completed my CAP 509 course in 1991, just in time for the worst recession in aviation, everyone that I knew then now has an airline job.
And the magic formula, perseverance, and a little bit of luck. A bit like life really.
Harry
p.s. I know , or know of, CAP509ers in every airline in the UK, myself include. Hope that removes some of the doubt, keep trying.