Keith Ford and Ayshea Johnson will probably be on duty so no fun for them, although Ayshea might sneak a puff on the odd cigar during her morning break.
Peter Carlin and the crew of Skydiver 1 will probably organise a dance competition, which Peter usually wins for some reason.
And what about those Moonbase Operatives. Well, the Moon might have no atmosphere, but I reckon the Leisure Sphere will be very festive and full of lunar 'Crackers'...(Yes, I know, corny, and not in keeping with todays progressive values , but hey, remember UFO was made in the early seventies!)
Straker will begrudgingly give Miss Eland Christmas day off , and will be probably visited by three aliens in his dreams who will just tell him to loosen up a bit. He'll just say, "Are you the SHADO's of the things that Will be, or the SHADO's of things that Might be?" (More corn I know, but anything Christmassy has to have a sprinkle of Dickens, doesn't it?)
And what about the aliens, themselves. Will there be a Christmas armistice or will they just work through?
Watch the skies...