Is this the bus stop you mean?
http://maps.google.co.uk/maps?f=q&hl...&t=k&z=19&om=1
that looks like a bus stop, the one which is a layby. I may well have gone through that too
my only hope is that usually at that point I am switching to the other side of the stream of cars, trying to go down the side near the central reservation, cos then I'm a bit cheeky and go in the right hand lane to go round the roundabout and then sneak in to the tunnel...