Under national regulations, if an online ride-hailing vehicle reaches 8 years of age from registration but its accumulated mileage has NOT reached 600,000 kilometers, what must happen to the vehicle?

1. It must be immediately sent to a vehicle salvage yard for physical destruction and scrapping
2. It must exit online ride-hailing operations (退出网约车经营), but does not need to be mandatorily scrapped if used as a private vehicle
3. It can continue operating as a commercial ride-hailing vehicle indefinitely as long as it passes annual emissions tests
4. It is automatically converted into a long-distance interprovincial tour bus