Sprwt does not allow one employee to have two shifts that overlap in time in the same job role. The message shows the conflicting shift's start and end. It also applies when adding an employee to an open shift (Add to Schedule). Shifts that touch exactly (one ends 17:00, the next starts 17:00) are also treated as overlapping, so leave at least a one-minute gap or extend the existing shift instead. When you create a shift with several weekdays ticked, none of the copies are saved if any one of them conflicts. Note: in the current version this overlap check compares shifts of the same role only — an employee given two shifts at the same time under two different roles will not be blocked, unless one of the shifts uses No assigned role, in which case it is checked against all of that employee's shifts regardless of role.