To be fair, I've always been dubious about the BBC's reporting (and by extension, all other news) since the floods in 2000. They reported from Uckfield saying the rain was still teaming down and people were worried that the situation was going to get worse, when actually it had stopped hours before.
I'm guessing this is on the road to the port which has various different speed limits (and trees). And yes, it was the ferry workers burning tyres on the roads to the port, not Eurotunnel, wasn't it?