Speeding

I was wondering whether you can help me, myself and my partner were driving back from Ireland early morning on x 2009. We were on a highway were the speed variation changed from 50mph then to 70 mph then remained 70mph on that road. We were stopped by one police offer were he claims we were doing 73mph in a 50mph zone. The police officer had pulled us over in a 70mph zone and we were sure that we had not been speeding.

The case description reads:-on x at x in the county of Conmwy drove a motor vehicle, namely large goods vehicle or passenger carrying vehicle , on a road namely x Eastbound, at a speed exceeding 50mph. Contray to sections 84 and 89(1) of the road traffic regulations act 1984 and schedule 2 to the road traffic offenders act 1988 ( what does this mean?)

The Police Officer caught us on a pro-laser gun, as we have asked for photographic evidence they state they can’t provide.

When we received the paperwork through the post and we sent back not guilty with our statement. We then receive in the post the following:-

• A letter that stated £450.00 fine and 4 points due to failure to attend court. If you read the summons letter it states do not attend the date on the summons if you plead not guilty as an alternative date will be sent to you.
  
  

I then wrote to customer service department at the courts were I asked for the case to be re-opened, which they did. We then attended court and they re-adjourned to x 2010  to be told we would be able to cross examine the police officer on that day. Can you help with the appropriate questions for the day? Or are there any legal questions we are entitled to ask?

Can you please help and give me advice as this has been going on since June last year.