I think the problem was that most folks can't keep up with all the days, weeks and months devoted to LGBTxxxxxxx celebrations and had no idea March 31st was an established celebratory day.
It's incredibly hard to keep track of Easter and why it changes and so on either. So I asked my partner "why is Easter always on wildly different days? (months apart even)" as they went to catholic school and I was not raised christian and they said probably something to do with a pre-modern calendar. Oh.