Sales order creation with Custom ATP category

Dear All,

We have a requirement to add certain sales order qty on top of the forecast and ensure these orders do not consume the forecast. We were able to bring these sales order types with different ATP category using CIF exit and not to include them in the category group for consumption however the issue is sales order requirement quantity is not getting updated by the deliveries created against them.

Below is the standard:

Sales order creation in R/3 - > CIF to APO

After delivery creation,Requirement quantity of sales order is updated as below .

In our case:

Sales order creation in R/3 -> CIF to APO

After delivery creation,Requirement quantity of sales order is not updated as per the standard scenario .which is doubling the overall demand.

Question - How can we ensure the deliveries created against these sales orders with ZM ATP category consume/update the requirement quantity of sales order like in the standard scenario , what is the Mapping done ?

Can someone please tell us how can we achieve this.

Thanks and Regards !!!

Uday