moving day
/ˈmuːvɪŋ ˌdeɪ/noun
The day of a move to a new location, especially to a new residence; (US ) the day on which leases normally expire in a particular city or region (in New York, May 1), frequently associated with household removals.
Origin
Mid 19th century; earliest use found in Workingmen's Advocate (New York). From moving + day.