To save time, you can make a copy of the current purchase order for the same purchases with the same supplier.
In every phase of the purchase order (Draft, In-progress, Completed, Closed) there will be a Duplicate PO button.
Click on that to process the copy. Then its copy will be made, in kind of Draft PO.
You can keep the information or make further changes to that copied PO.
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The copied PO will be automatically saved in the system. Feel free to make any changes here and Save.
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Note: The information on the Receive inventory and Purchase invoice will not be duplicated. You need to process those actions from the first step for that copied PO.