Nazareans Nasoreans their months have thirty days with five intercalary days to make a solar year), is ancient enough, being a festival of ancient Babylonia. They observe Ascension day (of Hibil Ziva returning from Hades) on the eighteenth of first Springmonth, the Great Baptismal Festival on the intercalary days, the Feast of the Egyptians apparently drowned in the Red Sea under Pharaoh (they were not really drowned, but escaped and were the forefathers of the Nasoræans), and a few other feasts. http://home.newadvent.org/cathen/10705a.htm