The contract only stipulates that there will be no training on Christmas and New years day. That doesn't mean you couldn't be in the middle of training during that time. That also doesn't mean you couldn't be in Montreal or Denver over this period as well. So... it very much matters if you're in the middle of class during the holidays. Another caveat is that if you've got vacation over the holidays... once you go to class for a new position, your awarded vacation blocks in your old position get dumped back into your vacation bank for you to rebid. So... if I was a "senior" FO and had a vacation slot with Christmas off, I wouldn't want to go to training either until after the holidays.