Bapi vs VA01 userexit differences

[fikretsomay]

Hi,

For some cases I want to change vbep-lifsp depending on conf. quantity.

While createing sales order from Bapi(BAPI_SALESORDER_CREATEFROMDAT2), availability check is executed after userexit_save_document_prepare. So at that user exit I dont have confirmed quantitiy yet, and also after that user exit I can not change anything. Do you have any advices ?

Thank you.

[Lakshmipathi]

Please brief what the Business requirement is