After Pricing Adjustments have been created and applied to Folders and Jobs they can be edited. However, existing jobs will not be affected by the changes only future jobs.
Editing Pricing Adjustments
Open Configuration and click on Central Options
Select the Price Adjustment that needs to be changed
Click the Edit record button above
Modify the details and Save Changes
Return to the Job File and the changes will be applied to the Folder as well as future jobs created