Changing Scheduling time using Object Dependencies

Hello Experts.

I have a scenario where my finished good is a variant material and obviously MTO.

I want to use dependencies to populate scheduling time that is based on Sales Order Characteristics and Machine (selected while creating production order)

as machine is not determined at sales order creation we can not conclude the scheduling time in sales order to over write it while creating production order.

what i am look for...

I want to keep my routing machine wise with a standard value Say "A"  that changes machine to machine. Rest of the variables I want to calculate in sales order say "B:.

For my scheduling time, on production order creation, i want scheduling time to appear as A X B (production of A and B)

So far I can replace A with B while creating a production order but I want to populate product of A and B (ie A * B) for scheduling while creating production order.

I will appreciate your help.

Thanks

CR.