When a job needs materials sent back, you can raise a material return request straight from the project — the tool assembles the PO's items and notifies the regional distribution list for you.

The Request Material Return dialog — reason box, with a note that the regional list is notified and you're CC'd.
As the dialog notes: “This notification will be sent to the regional distribution list and you will be CC'd.” The email includes the project details, the PO's line items, and a link back to the PO in NetSuite.
Don't have the project on the roster? Use the Manual Material Return Request panel at the bottom of the PO Generation tab — enter the Project ID and click REQUEST RETURN to open the same dialog.