I have just gone to amend my order for a delivery slot booked for next week (booked when Christmas slots opened in October!), only to find no trace of it on my account. The email confirmation link does not work either. I called them and they said the only way to fix it is for them to cancel the order and rebook it.... I am not filled with confidence that they will manage to do this given the slots have been sold out for weeks. If you have slots booked for Christmas, I suggest checking they still exist on your account!