The 2nd is never a day off in the US. The 1st is new years the day, the only official holiday.
Maybe somewhere with a different calendar entrenched might not care so much about Jan 1 though.
It is a 2 week period where fuck all tends to get dome because somebody, somewhere is on PTO or otherwise unavailable.
[0] https://www.opm.gov/policy-data-oversight/pay-leave/federal-...
https://www.opm.gov/policy-data-oversight/pay-leave/federal-...