I originally posted this on the other site back when I took the picture, and it resulted in a lot of confused comments, especially from Americans, eventually getting removed by overzealous mods. Either way, I promise you that this date does not exist, and has never existed.
Memories of the old shitty codebase I inherited that had a bunch of if/else statements to add a day every four years. Which, of course, isn’t even correct.
To be fair, by the time that code will fail, it won’t run anymore for a host of other reasons.