Hmm.. old thread, but just read this bit:
scott_mcavennie2 – Member
…They spotted me on the triple carriageway section of the A1 in Cambridgeshire and followed me for 14 miles. They knew that, as I was driving a hire van, I probably wouldn't slow down when it went down to a dual carriageway.
Maybe they were more worried that you apparently think there is a "triple carriageway" with a different speed restriction than a dual carriageway?