If full-time employees come into work early, stay after scheduled hours, or come in to the workplace on days off, the employees must be paid overtime if they are non-exempt and they work over 40 hours a week. the employees are not paid overtime because they are full-time. under the FLSA, the employees likely volunteered their services for that extra time. any extra time worked can be used to re-classify those employees from non- exempt to exempt.