From what I can find the item revision records make available a start/end date for changing components in an item, but I can't find anything that lets you handle it by the amount of component inventory left. For instance if we have a product that include 6 components but we change manufacturing to 5 components (basically combining 2 components into 1), is there a way to have the system use up all the 6 component revision first then switch to the 5 component version when the inventory levels fall to zero?