This is just speculation on my part, but the news from inside BA suggests there is a fair amount of uncertainty regarding the future of short haul and the likely impact the acquisition of BMI may have should IAG be successful in their bid. Once this has been resolved I imagine things will become clearer regarding exact numbers required for 2012/13.
If you are going through the recruitment process now or floating in the pool the two important factors in your favour are the arrival of the A380 and B787 are still going ahead as planned - this will result in a small but tangible increase in fleet size - and the folks who stayed on after the retirement age increased to 65 will start to head for the golf course full time over the next few years. There is clearly a need for a continual stream of new pilots into BA for the foresee-able future, as Wirbelsturm mentioned one of the biggest problems is simulator and training capacity. It's worth the wait once you get here
