Thanks guys, I mentioned it to Mum & Dad they were soooo very excited that they have organised time off & the extended family to come to their house for the day. They are first time Grandparents & have only seen him once. Also I know I will be miserable on Chrissy Day sitting around spending it on my own - so we are going to book our flights very soon.
Think I will go with the suggestions of having Christmas before we leave, the house will be decorated anyway & the tree up, so will open pressies, have lunch & so on when DH has a day off the week before.