Sad to hear that the air-drops have stopped, I heard about those and thought they must be such a morale booster.
Midwinter-gifts at UK stations is a long tradition, each base member makes one midwinter present in the weeks before the day. They are then wrapped anonamously and the base compliment take it in turns to select one from the pile starting with the youngest base-member to the oldest. Usually some momento of Antarctica, whale bone was a popular material on Signy where I was due to it's fairly commonplace availablity. I can see how it wouldn't work so well on a larger station though, I wintered with 14, then 13 men in my 2 winters.
We also had a whole week off rather than just a day - manly outdoor fun of various types with Midwinters Day as the highlight. Happy days!