Once I confirmed on google that Jan 26 was a holiday in Australia having something to do with the British discovering or first settling there in 1788 (as indicated by 24A) - given the meta prompt plus 35A and 50A, I decided I had to then to google to find out what aborigines thought about the holiday to see if that connected with the the prompt, which it did.
Though I did pick up a warning from some comments in the Tuesday Muggles meet-up that I had to go beyond the obvious answer, which helped keep me from falling into your trap for the unwary who ignored that DAY was intruding into the three theme answers.
Interesting way to inform non-Aussie folks about the controversy over Australia Day.