When you make a change to an existing recurring schedule you create an exception for a single occurrence of the schedule on specific day. The exception that is created only affects that specific day and does NOT affect any of the future schedules.
To create an exception:
1. Click on recurring schedule cell to open Job Edit dialog.
2. Make a desired change and click on "Done" button.
3. You will be presented with a message box with two options: "This Day Only" and "This and Future Occurrences".
4. Click on "This Day Only" to create a one time exception.
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