Multiple invoices needed based on individual shipments

Often times our customers Sales Orders are split into multiple shipments, that may or may not go out on the same day -- however, multiple trucks/loads due to size of orders.  I have an issue that when I run the invoicing job (R42565) that I get a single invoice for the entire portion of the Sales Order that was shipped confirmed since the last time the R42565 was ran.  I need a unique invoice for each shipment portion rather than a consolidated.