You edit the start time and end time for a schedule event when the condition changes. You can edit the start time for weekly events and single date exception events.
In WebStation, in the System tree pane, select the schedule with the event you want to edit.
In the Schedule workspace, click the schedule event you want to edit.
In properties dialog box, in the At box, enter the start time.
In the Until box, enter the end time.
Click OK .
Click Save .