The DA Form 6 is used as a duty roster.
So, back in the early 90s, I got stuck with the overnight Charge of Quarters duty at the company on Thanksgiving. Fair enough. Fast forward a month, and I got tapped for CQ for Christmas.
I took a loooong look at the DA 6 to make sure I wasn’t getting screwed.
Incredibly, the next year, the same thing happened. I had the duty on both holidays.
I went through an entire year’s worth of DA 6 trying to find an error. Nope.