Guy,This is just a business process change (the way this is worded). Your two lines that specify old and new code behavior are word for word identical (rightly so). I see your approach as a solution, but no change to Planning Optimization is needed. In addition to your planner following up manually with BOM changes I’d like to see a Plan Group of Superseding limited to only 2 lines since the priority value is confusing and now redundant.However, I’d prefer to see the “Use-up Engineering Change” capability seen in so many other ERP solutions. Here, effectivity dates are used and kept up to date (a change inside Planning Optimization MPS) to the date where MRP projects a transaction driving inventory of the old item in the Planning group negative. This does imply a likelihood of a small residual inventory of the old item, but so does your recommendation – easy to report on. Multi lines (e.g. these 2 new items supersede 3 items on the old BOM) would simply leverage phantom items in the plan group. No change to Planning Optimization and no manual step, A new checkbox column on the old and new BOM lines set to Use-up equals true and a new column declaring the same Use-up group (Plan Group could work, but why not).