All systems like Specs Gatso Truvello etc, have to be tested and approved to Home Office standards, good enough to stand up to the "Beyond reasonable doubt" test for prosecution.

When Specs were tested they only had approval for Start and Finish in the same lane, Why I don't know.
The loophole was known about in Notts when they first trialled here years ago.
It's not that the system can't cope with lane change it, was just not originally approved.

The approval also only covers the lane below or adjacent to the cameras, so a hard shoulder mounted camera cannot legally be used to catch lane 2 or 3, as widely publicised last year.

I assume since last years publicity about it they have been testing for approval with lane changing.

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