Hi Greg, I live next to this camera and my basic observations are:

- Yes it seems to be triggered by cars in both lanes (whether it is *meant* to is a different question, I guess)
- I've lived here for 8 years and still can't work out what it's for, though like you I was erring towards it triggering for amber-gambling
- There are some days when it goes off again and again and again, then periods where it doesn't seem to trigger for many days at a time

Anyway, I'm not sure any of that is helpful, but I certainly do sympathise.