I know what I was doing a few years ago (2014 I think) as I was reminded by Facebook. See below.
Here is Santa riding in on my mobile robot at the Raspberry Jam I organised, possibly Christmas 2014, distributing sweets to any passing youngsters and/or students. Sadly I never got to see Santa as whenever I was present he seemed to have left the room.
Can I count this as a contribution towards the Holiday Special 20? Perhaps I'll have to do something else as well. Pity I still do not have the mobile robot chassis.