Hi ,
Your requirement can be met by available Planning Strategies. USe 50- Planning with final assembly( or 52) . this is what it does.
-Forecast/Planned independent requirements are valid as Demand/For MRP
- MRP run will generate Requirment/procurement proposal for whole BOM, but Forecased item(Top level) plan order(Type: VP) will not be able to convert to Prod order. It is instrument to create dependent requirement for child items.
-Sales order will consume forecast (Backward/forward/Consumption days etc)
-Sales order qty/date will drive next MRP run to generate plan order for Top level FG. It will delete VP plan order & replace with PE(Make -To -order ) plan order.'
- You can define Material master--> individual /collective indicator to 2 for materials in BOM tree to delink procurement proposal/production orders for 1st level/2 level/ n level items.
- Finished goods stock will be tied to sales order when production completes
Hope this helps,
Jatin