Hello
Reading the BAdI documentation on transaction SE18 is always a good starting point to implement a BAdI.
The documentation explains that there are 2 ways of implementing this BAdI and one of them uses a subscreen for you to input the HR data.
It also provides the following information, which answers the second question:
IM_BF_CLASSIFICATION: Structure for classification of backflush
scenario.
Fields in structure IM_BF_CLASSIFICATION:
SCENARIO: Scenario for backflush
Field values
'LAGER' - Warehouse scenario
'KDAUF' - Backflush for sales order
'PRLOS' - Backflush for WBS element
TYPE: Type of backflush
Field values
'B' - Assembly backflush
'K' - Component-only backflush
'L' - Activity-only backflush
REPPOINT: Indicator for reporting point backflush
Field values
' ' - No reporting point backflush
'X' - Reporting point backflush
MODE: Backflush mode
Field values
'G' - Yield backflush
'A' - Scrap backflush
BR
Caetano