It's a holiday. And my day off.
Which means I'm out of the equation for working today. (There's usually a team selected for that on holidays.)
If it weren't my day off, there would be a 50% chance I'd work today. If I worked, I'd have the right to have an extra day off.
Christmas day and the new year (Jan 1st) also fall on a Thursday, my day off.
So, I'm gonna lose either one or two extra days off this end of year.