I'm in the 70mph lane, I don't need to overtake anything.

[@jimf4748]

Whats the 70mph lane? I thought you could do 70 in any lane.

[@Marwolaeth01]

You're correct, the other lane is for overtaking or, if an A road, also turning right. When not overtaking you should move back into the left hand lane, traffic permitting.

[@ian666if]

There's no such thing as the 70mph lane. I suggest you read the highway code and take some more driving lessons.