Is that the date before or after all the calendar changes that have occurred since then?
I don’t know, but this statement sure threw me:
All freedom loving people need to honor this August occasion.
The calender only changed about 12 days, and that was in 1752, to rectify the accumulated error since the time of Julius Caesar. The error would have been less in 1215. Either way it was a June occasion, not an August occasion.
I have NO idea but is it really important?