Johnny - BA have sent their cadets to Kiddlington, Bournemouth, Jerez and Cranfield and West Michigan in my memory.
They ain't loyal to one or another and regularly move around to secure the best terms.
REMEMBER that you are not BA. BA can waltz in the door and get a very different deal to the one you can sign up to. Their cadets get modified ground and air syllabi. They get extra bits added in and work to slightly different timescales. Their cadets might only be trained by the more senior instructors, they might have priority access to some resources. They will have coaching by BA staff charged with administering the scheme. They will be subject often to more thorough examination and feedback through BA stipulated paperwork and mechanisms.
Just because BA or any airline choose school X for their cadet scheme does not mean school X offers the best 'open to the general public' Frzn ATPL course.
When I was an innocent young Wannabe I used to be impressed by the fact that BA chose School X for their cadets.
Then I paid for my own training. Then I became a flying instructor at Jerez. Now I work in the airline business.
I realise now that I almost made the mistake of choosing a training provider because BA had. There may be many good reasons for choosing OATS or Jerez, but, because BA have used them recently is not one of them.
WWW