Route Determination

Hello Guru's,

I just want to know if it is possible to force system to redetermine route every time I change Request Delivery Date, Any user exit?

Actually what is happening right now

I have maintained three routes against each Shipping Condition and with the help of a User exit system is selecting appropriate route based on Request Delivery date and gives us confirmed Schedule line.

Now if I change delivery date from 15th to 12th, I want system to do that process again and select the appropriate route.

Any thoughts please? Mind you we always meet Customer Requested Delivery Date

Regards,

Khawar