I think I just got caught speeding by a mobile speed camera, was doing 35-40 in a 30

But can anyone inform to the legalities of the mobile speed camera as im not sure if they would be right in giving me a ticket, just some queries really.
-First I was driving towards the camera, it is correct they can catch you for speeding even though they were on the other side of the road?
-There was a bus pulled up at a bus stop obstructing id say half the cameras view, would this ive a true representation of speed?
-They had located themselves on top of a hill with the camera pointing out to it, would this give a true reprensentation of speed as it is an uneven road and not a flat surface?
-When I went past the officer didnt have an type of high visability clothing on and when I came back she did, it is a hot sunny day, do they have to wear the high visability clothing when using the equipment?
-They were community officers are they allowed to use speed cameras?
Just some things I was thinking about, if anyone could answer one if not all of them if would be much appreciated.
Thank You.