A schedule-triggered flow starts from a configured schedule and evaluates the eligible record population. It differs from a scheduled path attached to a record event. The org's time zone and the calendar date are part of the requirement, so a user's display locale doesn't decide when the schedule runs.
Keep the start conditions narrow. A nightly case review should not keep changing closed cases, and an overdue check needs a deliberate inclusive or exclusive boundary. Test records before, at, and after the due date. This simulator exposes a local schedule date and debugable canvas; it doesn't operate a hosted scheduler. A real release also needs the correct execution user, permissions, limits, monitoring, and an operational owner.