Sounds like a close one, good on the WVM ? Touch wood the only incident i've had with a left turning HGV was when one overtook, I must have been in front of him for a while, in the regular lane and started to drift in to the bus lane, where I was to undertake a queue. Typically there was railings on my left so I could have been hemmed in or worse but give him his due though when I tapped on his cab door he stopped and was quite reasonable when I explained why I'd did it.