Planned order not considering Processing Lead time while calculating suggested due date

Summary:

Plan type : Constrained Plan

A back-to-back sales order for itemX was created with order date and ship date as today's date. This sales order was collected to the planning work area.

After plan run, Sales Order for itemX and corresponding Work Order for itemX are available in the plan. However few of the raw materials(components of itemX) are not having enough onhand so plan has generated Planned Orders for these raw materials. The start date,dock date and due date of these raw materials are also today's date. All the raw materials are having a pre processing lead time =1 , processing lead time = 2, post processing lead time=1.