A staff-side overlap occurs when a support staff's shift overlaps with one or more other shifts that he/she has previously submitted. An overlapping shift must be resolved before it can be submitted.
Overlap testing is only run against shifts that have already been submitted. In other words, if two shifts in Draft overlap each other, the overlap will not be flagged. However, as soon as one of the shifts is submitted, an overlap will be flagged on the remaining shift.
When resolving the overlap, only the Draft shift can edited. Previously submitted shifts cannot be edited.