Essene Calendar Year. As prescribed by the book of enoch and used at qumran (dead sea scrolls) showing a 31st day added every three months giving a year of 364. This means that this system always makes the 3 rd day of the week.
The year of this calendar consisted of seven pentecontads. (interpreters dictionary: The essene calendar, divided into 12 months with 30 days each, added four extra days dedicated to seasonal transitions.