June 31st: The Lost Discordian Holiday?

My Papa (paternal grandfather), was born on June 31st. Can any of you see what is wrong with this picture? There isn't and never was a June 31st! Why is that?

I believe it was removed by Greyface's minions when they threatened the Gregorian calender bearers because it was a Discordian Holiday. That is the reason why the Discordian calender was introduced! I petition the POEE to add the extra day to accommodate whatever holiday was celebrated that day! Fnord.