One of our customer has outsourced the production task to multiple vendors. Each vendor will assemble parts in sequence to get the released products. Currently while executing MRP, all the planned purchased orders for sub contract vendor is getting schedules parallelly by ignoring the routes configured. There is no method available to manage the vendor operations sequentially and the planned purchase orders are getting scheduled with backward scheduling from the delivery dates.

Lets say for example, for making a mobile phone, Vendor A will assemble the chip set and send back to customer.
Then Vendor B will assemble the display in the chipset assembled by Vendor A.
Then Vendor C will assemble cover in the Chipset and Display assembled by Vendor A & B.
Hence after executing MRP, all the planned purchase orders are expecting to scheduled one after another from Vendor A to C.

Kindly provide facilities in system to handle above scenario which would cover wide range of customer requirement and help supporting improve customer business.