I thought I recalled more about Lady-Day:
https://www.historic-uk.com/HistoryUK/HistoryofBritain/Give-us-our-eleven-days/The UK switched from the Julian calendar to the Gregorian calendar in September 1752 to align with most of Europe. The Julian calendar was 11 days behind the Gregorian calendar, so to account for this, September 2, 1752 was followed by September 14, 1752. The official start of the year used to be Lady Day (25th March), but the loss of eleven days in 1752 pushed this back to 5th April. Another skipped day in 1800 pushed it back again to 6th April.
There supposedly were riots in UK over the lost 11 days...with demonstrators demanding the 11 days be somehow returned to them and speculating that it would lower life expectancy.
This apparently applied to the American colonies as well: In England, Wales, Ireland and Britain's American colonies, there were two calendar changes, both in 1752. The first adjusted the start of a new year from 25 March (Lady Day, the Feast of the Annunciation) to 1 January, a change which Scotland had made in 1600.
And:
England's calendar change included three major components. The Julian Calendar was replaced by the Gregorian Calendar, changing the formula for calculating leap years. The beginning of the legal new year was moved from March 25 to January 1. Finally, 11 days were dropped from the month of September 1752.
The changeover involved a series of steps:
December 31, 1750 was followed by January 1, 1750 (under the "Old Style" calendar, December was the 10th month and January the 11th)
March 24, 1750 was followed by March 25, 1751 (March 25 was the first day of the "Old Style" year)
December 31, 1751 was followed by January 1, 1752 (the switch from March 25 to January 1 as the first day of the year)
September 2, 1752 was followed by September 14, 1752 (drop of 11 days to conform to the Gregorian calendar)
