And I'm pondering what sort of annual festivities to stage. Especially with an imaginary world and an imaginary religion. And doubly especially when one sort of celebration contains Valuable Information so they aren't all clutter, or local color, according to what you term it.
This is because it commemorates a historical/legendary event of enormous importance to the world in general, which I think a good enough reason when the Information, while Valuable, is not very plentiful and somewhat misleading. On the other hand, I think it also means that I need more festivities just to avoid having a large neon arrow point at this one, saying, "THIS IS VERY IMPORTANT STUFF HERE." It lacks subtlety, having the only instance of something being Very Significant indeed.
So having the characters manage to miss all the rest would not exactly work, which means I have to invent them. . . which probably needs a few more historical events to be commemorated, and probably some religious festivals.
And, of course, I have to tie them into the story. Probably by having them making talking to people and getting stuff done more complicated.