It used to be the case, that of the 10,000 professional pilot licence holders in the UK or so at the time, BA employed about one third, the RAF accounted for another third, and the rest worked for what was termed the independents.
Having being the employee of two different subsidiary airlines of BA over the years and having on both occasions found myself redundant, I would anticipate that for those considering working for Open Skies, the future might not be what they anticipated.
But on the other hand; if BA pilots were to go on strike and in the event that BA would hire on contract or employ directly pilots to fly their otherwise grounded fleets, I would have no hesitation in working for BA, on my terms. Given that of the aircraft type ratings I hold, four of those types are currently operated by BA, I may of some use to them.
It would be a bold move from Willie to allow a strike to go ahead; but if he did and given that the proportion of RAF pilots available to airlines has reduced and that the proportion of pilots working for independents has probably increased, I could foresee a situation where BA crew it's aircraft from a mixture of strike breaking BA pilots (probably management, the ones most difficult to replace) and new direct entry pilots.
It should be remembered, that when President Reagan sacked all the US Air Traffic Controllers, the USA did not grind to a halt.