Luke Petrolekas

No, an internal system does not need to be created. The ICalendar spec can absolutely handle the case of "last day of month" and "last workday of month" scenarios. Also...

Ok, I put my foot in my mouth back there, you're correct. I did manage to find this, which looks to be the exact same question. https://stackoverflow.com/questions/35757778/rrule-for-repeating-monthly-on-the-31st-or-closest-day It's supported by...