Growing up 12/31 as New year’s eve always confused me. I am Jewish (Reform) and the Jewish year starts in Sept or rarely, Oct. School starts then. The new cars used to come out then. The new TV shows came out then. I thought Sept was the start of the year.
As to pcolli – that makes a 6 month year? I know that before the change to the “new style” calender, the year numbering changed in mid March.