Hi Expert!
My goal is to substitute items material in case there is insufficient stock at the time the Batch Order is created.
I have a setup in the Item Formula, where the 2 component items in the formula I give the same Plan Group 'Additive' and Priority 1 and 2. (img 1)

When a Batch Order is created, the Item material which Estimated qty is filled is the first item. Even though the first material has no stock, and the second material has stock. (img 2)

I feel that I have taken the right steps in setting the Plan Group and Priority in the Formula.
But the results that appear in the OP's Formula are not as expected.
Is there a step that is missing or not quite right? Please advice and solutions.
Regards,
Antony