Use discipline to enforce your no-Overtime policy

Q.  We temporarily allowed an hourly employee to come in early and take work home at night. We paid her for overtime on both ends. But now we’ve promoted someone else and told the hourly worker to stop coming in early and taking work home. She said she prefers working early and still does (plus she skips lunch) but reports for just 40 hours. Is she setting us up?—L.B., New York