UPS requirements dictate that they will only accept shipments to valid street address and do not deliver to PO Boxes. The United States Postal Service (USPS) must be used when shipping to a PO Box. However, orders shipping to a PO Box and a carrier of UPS may be loaded into Infoplus from an external source. To address this, use triggers to change the shipping Carrier on orders that fall into this category.
That’s all there is to it. New orders that contain a PO Box in their Ship To street address and have UPS set as the Carrier will now automatically have their Carriers changed to USPS.