Yes my answer to the earlier question covers your question. (I noticed there is a typo in that answer. I suggested that failure to provide driver’s details results in a prosecution under S165 of the Road Traffic Act. In fact it is S172. S165 deals with police powers to seize vehicles). The prosecution has no obligation to produce any information regarding the calibration of the device unless and until you plead not guilty in court. Even then they are under no obligation to do so unless you launch a defence based on alleged inaccuracies concerning the device. The devices are assumed to be working properly unless you can prove otherwise. If you fail to do so it results in an expensive day out.
As for your specific situation, DanDan, you don’t say what stage in the process you are at but if you have not yet named yourself as driver you need to get a shift on. You have 28 days to respond and the clock does not stop should you raise any queries such as those you mention. If you fail to respond in time you will be charged under S172 and that carries six points, a hefty fine and insurance grief for five years. This is irrespective of any defence you may have to the speeding allegation. You say you have pleaded “not guilty”. I doubt at this stage you have had the opportunity to enter a plea as I doubt court proceedings have begun. The prosecution are unlikely to provide the information you have requested unless and until you plead not guilty in court. Then you need to be prepared to prove (on the balance of probabilities) that you did not exceed the speed limit as alleged. Can you do that? I would suggest you forget about calibration certificates or the positioning of the camera van (neither of which provides a defence). Just out of interest, what was the prevailing limit and the alleged speed and how fast do you think you were travelling?