If a footprint to produce reactor grade Uranium already exists, it could mask the footprint for something else. It might be easier to deplete a small percentage

If a footprint to produce reactor grade Uranium already exists, it could mask the footprint for something else. It might be easier to deplete a small percentage of Pu240, than to enrich reactor grade Uranium (4% U235) to a highly enriched form (90% U235). How would the volatility of Pu240 effect separation? Not sure.