Firstly, I don't know why CAS is miffed as it would have not even come out of his budget - 33 Sqn work for JHC who get their budget from Land Command i.e. the Army!
Secondly if they took the opportunity to do some adventurous training then that sound like efficient use of time and resources. (I am not going into the justification for adventurous trg here.)
Thirdly where can you find real mountains in the UK that compare to those on the continent? Where can you guarantee the snow?
M609 I think you'll find that BDU is full for the winter trg period as far as JHC is concerned.
GB2