Dependent demand issues with end item substitution, wrong pegging in ASCP

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Issue: Independent demands are pegged to supply and given high priority over dependent demand

We are using end item substitution and in consumer industry

Customer C1 buys Finished good FG1

Customer C2 buys FG2 (FG2 is nothing but FG1 with a component COMP1 )

In item substitution we have

FG-->FG1 for customer C1

FG-->FG2 for customer C2

As you could see FG1 is the component of FG2. Due to this oracle pegs wrong demands to supplies

ASCP pegs all its supplies to independent demand from Customer C1 / FG1 and then recommends planned orders for FG2/C2 even though the schedule dates for FG2/C2 are earlier and forecasted