The only reason BA need more pilots and are opening DEP is they simply got their numbers wrong. How? I don't know but I guess it's all to do with new aircraft, delayed deliveries, delays to retirement of 767, the biggest flying program ever. I think there has been uptake of part time contracts and also a reduction in people doing overtime.
A lot of guys in the very recently abolished DEP holding pool (we are talking less than a year here for some folk) predicted this as being the case. Because it was also the case back in 2008. I'm a firm believer that quite a few in pilot recruitment regarded it as being the case too. So another DEP campaign, more time and money. And then what? A job, a hold pool position, no job? Only Airbus pilots are good enough when in times previously it was the person not the rating that was good enough (I know the last campaign was mostly type streamed). And don't give me the training risk, shortened bridge course argument. BA transfer it's own crew from Boeing to Airbus back to Boeing regularly. Plus they still recruit military pilots with zero commercial experience plus FPP guys with diddly squat. Who really decides things in BA? People with actual operational or training experience? I doubt that. IAG want all the 'leanness' of a modern day airline but I reckon the ivory towers structure of a government owned institution still exists in places.