I would like to share the process that i had come across with the following scenario:
Master data Setup:
The PPDS PPM is created directly in APO and is not transferred from ERP via CIF. There is no There are no BOM and production version for this material in ERP, instead the components are planned directly in APO.
Now now when we create planned order and transfer it to APO , the order does not have requirements in it. More technically, when we transfer order to APO it has the PPDS PPM attached to it automatically. However the are deleted , this is by standard. The function module /SAPAPO/DM_ORDER_MERGE_CIF_APO has the concept of implicit_delete that is set to true. This means all the components of the order are expected to be sent to APO, and in case there are no component found from ERP then system deletes it.
SO this is by standard that we expect the requirements missing in the APO order and this is not an error