Changing Approval Hierarchy in iProcurement

Hello

I have the "Can Change Approval Hierarchy" flag enabled for the Purchase Requisition. However, when I log into iProcurement to create a purchase requisition as a user, they do not have the option to change the approval hierarchy from the default specified in the Document Types window. Now if I create the requisition via forms in Purchasing module I am able to change the approval hierarchy. Does anyone know if it is possible to change the approval hierarchy in iProcurement or can that only be done through the requisition form in Purchasing?

Thanks,

Anthony