Need To Change the receipt routing from Inspection Required to Direct Delivery for all Approved open

Requirement:

We have many Approved open non received-Purchase Orders PO in our system. our client requirement is need to change the receipt routing method from Inspection Required to Direct Delivery for all these PO.

Here the condition is Client is not interested to go for Re approvals of all these PO

Please find below scenarios & suggest the solutions

1.PO s are Fully Approved- Fully not received

2.PO s are fully Approved- Partially Received

3.PO s are in process-Fully not received

Kindly please check and provide  is there any API to meet our requirement and give us the best suitable solution.