To me it’s just the equinox. Happens twice a year. The spring one is associated with new beginnings so it sort of makes sense to start a year then which beats January 1st I suppose. Happy equinox everyone.
The Julian calendar used to begin the year later in what we know as the year. :^)
[snip] WHEREAS the legal Supputation of the Year of our Lord in that Part of Great Britain called England, according to which the Year beginneth on the 25th Day of March... [/snip]
[snip] The Julian Calendar, hath been discovered to be erroneous, by means whereof the Vernal or Spring Equinox, which at the Time of the General Council of Nice in the Year of our Lord 325, happened on or about the 21st Day of March, now happens on the 9th or 10th Day of the same Month... [/snip]
https://dfns.dyalog.com/n_British_Calendar_Act_1751.htm
additional:
https://dfns.dyalog.com/n_Gregorian_calendar.htm