Sales order route determination user exits

Hi Experts,

I have searched the forum but couldn't find an answer for this issue.

The user exit USEREXIT_SAVE_DOCUMENT in MV45AFZZ is being used to fill the custom route field at the sales order item.

This is working while creation of the order.

But, in change mode when we remove the Delivery block and save the sales order , the route number is different in table VBAP compared to what is being determined in USEREXIT_SAVE_DOCUMENT.

Is there any other user exit which is triggered after MV45AFZZ? Please help.

Thanks Ram