Well now you see the consequences of 'driving to the conditions' !!!!!
There is usually a reason its a 30mph limit, maybe not obvious to you, but THINK. It must be a built up area, so pedestrians, kids running out etc,etc Watch the TV ad, hit someone at 38mph they have a lot less chance of survival than 28mph, that is why the speed limit is there to PROTECT THEM.
The white lines are there so they know what speed you are going at from when you triggered the speed sensor previously, so they already know you are speeding. The camera gas got you.
Just wait for the ticket and expect to dig into your pocket for a fine or a course.
My tip to you SLOW DOWN and if you think you are a good driver, take the RoSPA Advanced Driving Test, I bet you don't even pass, a gold is at the standard of a police driver without the pursuit element.