I was told they only guarantee for 6 months when I had a fault develop with a bag just after 6 months. As it only cost about £12 (+p&p) I didn't bother to follow it up (although I put a post on here about it at the time).
Perhaps I had an "awkward" CS person, so I hope you have better luck.
As your dog was sold as an Xmas present it should be assumed that it wouldn't be opened until Xmas, regardless of how difficult the box was to open.
You could also tell them "a dog is for life, not just Xmas" lol (or perhaps not!)
