As far as I know, there are not so many (most commonly used) permutations …
(YY)YY-MM-DD +
DD-MM-YY(YY) +
(YY)YY-MM-D(D) +
D(D)-MM-YY(YY) +
… and the written word of the month between the day and year.
… with a dot or “-” as separator. And there are existing validation methods out there.
I’m glad to hear this. This is very kind and I appreciate this.
Discourse requires it’s own (at least virtual) server and is very powerful by default. Most of the features are way better than previous stand-alone / plugin LAMP solutions, I’ve tried dozens over the years. Some people might call it the “Eierlegende Wollmilchsau”. 
For the first time in history we’ve got a open source solution, I would bet, this could work at least the next 10 years. Perfect for knowledge base use-cases …
Over the past years, I’m maintaining my instances in the most reliable way. I guess, most of us experienced broken rebuilds, blank pages and other major issues … at least for a couple of minutes up to several hours. That’s way, I prefer official plugins more than other great plugins, like this one. Events is amazing, but I don’t like to change all of the topic names to have a unified scheme. All of my topic names follow the scheme “DD.MM.YYYY - Name” (sometimes with comma instead of - ).
By the way: There is small usability issue.
I’ve experienced an issue with “long” category and subcategory names with the new tabs “calendar” and “agenda” next to it. The topic buttons on the top right corner creating a line break. Especially on mobile devices. Therefore, I’m also looking for a setting to enable a drop-down menu for both new entries OR by merging both views in one tab. You might know, like the list view of this calender on the top right corner.
What do think? 