Reserve Incoice in External Production

In the External Production, after the PO is made, we need to make an advance payment to the supplier, for this purpose we use the "A/P Reserve Invoice".
The SAP "Reserve Invoice" is a document that does not post stock movement, it only creates the posting of the debt with the supplier to be able to issue the payment. After that, the entry of material is made against this "A/P Reserve Invoice".
In Beas Third-Party Operation Process, this document (A/P Reserve Invoice) close the process, and close the availability to do the "Goods Recepit from the external Supplier"