When completing an overtaking manoeuvre, when is it safe to return to the right-hand lane?

1. When you can see the entire front of the overtaken vehicle in your interior rear-view mirror and have signalled right
2. Immediately after your front bumper passes the front bumper of the other vehicle
3. As soon as you activate your right indicator, regardless of distance
4. Only after you have travelled at least 500 metres ahead of the vehicle