As I've said on another thread, it is quite impossible to make any reliable predictions for when things will pick up while the aviation world is so jumpy, and world events are still directly affecting traffic loads. When military action is over, and people have stopped 'seeing' terrorists in every shadow, analysts will be able to start giving sensible predictions about the rate of industry recovery. That will obviously be related to both passenger confidence and overall economic confidence, both of which are shaky right now.
It will improve, and it will eventually recover to the line predicted before the 9/11 events - so there will be jobs, eventually. Once BA has some idea of the shape, health and future of their business, they will have to restart training sharpish. They still have a large number of pilots approaching retirement, and they can't afford to let their pilot establishment drop below the fleet requirements. BA has, for a long time, a policy of simultaneously taking in both experienced and ab-initio pilots, and I see no reason for this to change. So, even before any return to pre-September aircraft numbers BA will need new people. I personally doubt that you'll be in limbo for more than 6-9 months, but, of course, I could be wrong!
The main thing is, don't lose hope. But don't expect any great amount of information at the moment when no-one knows how it's all going to pan out. We're all using the same very foggy crystal ball!