Random question - Luton airport

[danjama]

I was driving out from Luton airport two days ago on the stretch of road with roadworks heading up to the m1. I was moving with traffic, speedo on 38 so about 35 as mine over reads at the moment.

Didn't see the police scamera. But I'm not sure if that's a 40 limit as on the opposite carriageway, or lower due to roadworks.

Anybody know?