Definition of a Workday/Workweek
A “workday” is defined as a consecutive 24-hour period beginning and ending at the same time each calendar day. The employer is free to define the time at which the workday begins and ends, and may also specify different workdays for different employees. If an employer does not specify a workday, the default workday begins and ends at midnight.
A “workweek” is defined as any seven consecutive 24-hour periods, beginning on the same calendar day each week, and starting at any time during that day. The employer is free to define when the workweek begins and ends, and may also specify different workdays for different employees. If an employer does not specify a workweek, the default workweek is from 12:01 Sunday to midnight the following Saturday.
Once the workday or workweek is established, the employer cannot change the workday or workweek unless that change is intended to be permanent and it is not designed to avoid overtime obligations