What you're saying is apparently true for the International Fixed Calendar, but not the Sol Calendar. According to [1], the first (and second and third...) of e

What you're saying is apparently true for the International Fixed Calendar, but not the Sol Calendar. According to [1], the first (and second and third...) of every month in any given year is the same day of the week, but the mapping changes every year. [1] https://calendars.fandom.com/wiki/Sol_Calendar https://calendars.fandom.com/wiki/Sol_Calendar