Commissionly gives the possibility to process opportunities for custom period. To accomplish this:

1. Select "Opportunities" from the main menu

2. Navigate to the blue 'Process' button

3. Choose Background Process Filtered Opportunities

4. Pick the desired status or statuses if applicable

5. Specify the date range (period) for which you intend to process the opportunities
6. Click on 'Apply' 

7. Confirm by clicking on 'Select and Process'