Revalidation - Process

Dear Experts,

Good morning.

As per business requirement, revalidation approval process needs to be perform as like following condition. How to achieve in standard functionality. Kindly Guide me.

First 5 days from promised date -             Self-Approval

Next 5 to 10 days                        -             1st Level Approval

After 10 days                               -             2nd Level Approval

Any Shipment Change - 1st Level Approval.

Thanks & Regards.

Babu J