To be honest, I kind of completely forgot this was even a thing. Or didn’t know in the first place.
Either way, I had no idea it was going on until a few minutes ago (when the day was nearly ending).
I entirely agree that having 3/14/16 (or 3/14/15) as the Pi Day is horribly American-centric, but it just so happens that 31/4/16 (or 31/4 anything else) is just barely not a valid calendar date under the European DMY format. April does not have 31 days. Sorry.
However, 31/4/16 (or indeed 31/4/15) is a totally valid date under YMD format, which is what everyone should be using anyway because it’s the most mathematically logical (though to be fully mathematically logical, it should have been 31/04/16, and that doesn’t really work).
So I’ll set an alarm to April 15, 2031, to do something nice on 9:26:53 AM. (And again on 9:29:20 AM, to celebrate the famous approximation.) I was planning to write some letters to the early 2030s anyway.
(On April 15, 2031, my younger brother will be several months older than I am today. Which is extremely weird to think about. I wonder if he’d have a job by then… or a wife, for that matter.)