When using the Drop Ship function to link a Sales Order to a Purchase Order, the lines on the PO have the SO number and the lines of the SO have the PO number. This link seems to disappear entirely once the orders are invoiced. I cannot find entries on the Posted Sales Invoice Lines or Header tables that include any data to link to the related PO, Posted Purchase Receipt, or Posted Purchase Invoice (or vice versa).
Am I missing something or does Nav really wipe out this extremely helpful information?