To change the raw materials on a manufactured product that is set to affect inventory at billing time, it is recommended to add a brand new product and include the new formula.
Using this method affects inventory correctly if any Invoice that used the original manufactured product is later voided or reversed. If invoicing against the original manufactured product and changing the formula and voiding or reversing the Invoice, the raw materials inventory will be affected by the quantities set in the new formula, not by the quantities from the original formula.
