iProcurement - change a requisition to add a new line when PO is already generated

Hello Colleagues,

We run eBusiness Suite Financials 12.1.3. Users use iProcurement to raise Requisitions which once approved are automatically transformed into Purchase Orders. Users then issue the POs to suppliers.

Question: Users wish to have the ability to change the existing PO to add New Lines. Currently they can change the PO through iProcurement to cancel lines, update quantities, prices, etc. But they cannot change a PO to add a new line using iProcurement.

Can you please suggest if it is possible for an iProc user to change a PO to add a new line? (without using core PO module or buyers).