Need by date on PO requisition released from ASCP

Hi,

The question I have is how the need by date on the PO requisition is derived when I release a plannned order (unconstrained Plan). When the item on the planned order has a suggested dock date < suggested due date (due to post processing lead time) I would expect the need by date on the released purchase requisition to be equal to the suggested dock date on the planned order, but my testing shows that it is using the suggested due date.

Thanks