Speedbird,
Who knows?
From what I'm reading OAA seem to get you through faster than CTC, i was less than 6 weeks from application to confirmation of passing stage 3 (still awaiting on which route i've been given).
From reading on here CTC don't open up dates to stage 2+3 that often. Possibly because they are running Virgin/Flybe and there own assessment as well as Easyjet.