New York Correction Law Section 500-L - Release on holidays, Saturdays and Sundays.

 500-l. Release on holidays, Saturdays and Sundays.  When the date of
  release  from  imprisonment  in  any  county jail or jail farm, any city
  prison or workhouse, falls on Saturday or Sunday, it shall be deemed  to
  fall  on  the preceding Friday. When the date of such release falls on a
  legal holiday it shall be deemed to fall on the  preceding  day,  except
  that when such legal holiday falls on a Monday the date of release shall
  be deemed to fall on the preceding Friday. This section shall also apply
  to  civil  prisoners  confined in any jail or prison. This section shall
  not apply to a sentence of intermittent imprisonment imposed pursuant to
  article eighty-five or paragraph (d) of subdivision two of section 60.01
  of the penal law.

Last modified: February 3, 2019