Subcontract and MRP

Hi All,

Please help me in the following scenarios.

1. MRP creates requisitions and reqs are converted to subcontract PO with delivery to next vendor(SC vendor option in PO item line),

But if we change the date of the subcontract PO delivery date and run MRP, it is creating new requisition without considering the existing subcontract PO.

eg: Finished Material - A

Component - A1< -A2< A3.

Vendor - V, V1, V2, V3

A3 procured from V3 and shipped to V2. V2 makes A2 using A3 and ships to V1 and so on. If we change the subcon PO date of vendor V2 and re-run MRP, sytem is creating new requirements to meet the new date.

Is there any setting to consider Subcontract PO/stock in MRP.

2. Material is shipped to subcontract vendor. On inspection some materials need to be scrapped.

My client want to move the material to a scrap storage location and do a transfer posting to another material from the scrap location.

Which mvt type i can use to move material from subcontarct location to subcontract scrap location.

Can somebody please tell how this scenario can be managed in SAP.

Thanks

Balu