planned orders creation from msc_supplies.

Hi here is what I need to understand.

In our system, the demand data is collected, ascp planning process has been run and i can see data in msc_demands table with appropriate plan_ids. The disposition id in this table is not null and I can even query with the same disposition id in the msc_supplies. However my understanding is that a planned purchase order is created based on a record in msc_supplies. but i am not able to see any planned orders either in PO tables or WIP tables, in fact I dont see any planned orders in our system(only standard orders). what am I missing here, can