The PO query change screen can be used to edit purchase orders that have not yet been fully received and are not currently in the receive items screen. Changes will only be able to be made to purchase orders that are still open. (The only exception being doc notes). Also if a PO is tied to one PO or Project you will be able to convert that PO from a regular to a drop ship PO in this screen.
PUR > PO Processing > Enter New POQuery
Note: One issue that is often brought to support is users are unable to edit a purchase order that is still open and they do not know why. Usually this is caused by someone pulling the Purchase order into the receive items screen and just closing the screen without pressing clear. When this happens close the query screen go to Receive Items and press F8 key, use your arrow keys to navigate until you find the PO you are looking for and then press the clear icon on the top right of the screen. You will now be able to edit the PO.
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