When overtaking another vehicle you should NOT move back in front of it, unless

• A. The driver of the vehicle signals it is safe to do so.
• B. You can see the overtaken vehicle in your rear vision mirror.
  Explanation:

  "Moving back into the left lane early may mean you hit the vehicle you are overtaking. It's particularly important if you are driving a longer vehicle to wait until you can see the overtaken vehicle clearly in your rear vision mirror."
• C. An oncoming car appears over a hill.