Prior to about 705 BC all the civilizations with advanced astronomy (Israel, China, Mayan) had the Earths year at 360 days, consisting of 12 months of exactly 30 days each. (Quite a testimony of Divine Creation. It has been recently asserted that a large rogue planet pulled the earth further away from the sun about 705 BC causing the increased year. See Isaiah 13:13 and 2nd Kings 20:11) My question is, prior to 705 BC, when the calendar and year was 360 days, as 1st Samuel 20:27 says that a New Moon Celebration is 2 days, how did this effect the weekly Sabbath? Was the day after the 2nd day of the New Moon always the Sabbath (did the New Moon always fall on the same days of the week, such as Thursday and Friday), or did the two day New Moon celebration sometimes fall "randomly" in the middle (or elsewhere) in the week, or was the New Moon always immediately before or after the weekly Sabbath to always have a "Three day weekend" once a month? (Feel free to send an image of a calendar showing how the New Moon and Sabbath worked on a 30 day month in a 360 day year.) Thank You very much for your time and thoughts!

I'm not familiar with the historical theory which you mentioned. It is not found in the Jewish sources, which state that sometimes Rosh Chodesh was 1 and sometimes 2 days, just as we do today. Similarly, generally Rosh Chodesh would fall on all 7 days of the week, just as today.