When the Doctor is trying to cut the cables to prevent the rocket from launching, the beeps of the countdown indicate that the display should be clicking down from 15 to 14 when the camera switches back to the display, but it actually shows the countdown going from 10 to 9. Then listening to the bleeps further, the countdown should be at -2 when the display shows it going from 2 to 1, and the Doctor stops the countdown after another bleep occurs, which should have been too late.