Free Traffic Legal Advice

Hello I'd be grateful for some advice.

I received an NIP for an alleged speeding offence taking place on 26/9/2025. The offence is exceeding a limit of 30mph, according to a mobile speed camera van recording 36mph on a stretch of road with a steep gradient (van was at the bottom of the hill). I viewed the evidence. Two photos show the car and differing speeds- 36mph and then 35mph. There is also video footage showing 35mph and the speed decreases to 31mph and then no speed is shown as the video ends (I can no longer access the portal to view).

The COFP is three points and £100 fine (received 12/10/25) Are there any grounds to contest this? The speed is decreasing, responding to speed limit advised by end of the footage?
 
(P.s. awareness course completed in May 2023, less than 3 years ago).

You cannot contest an offer of a fixed penalty. You either accept it or reject/ignore it.

If you do that you will be prosecuted in court where you can contest the charge by pleading not guilty. Nothing you have mentioned suggests you will be successful. If you are convicted you will be fortunate to leave with any change from £1,000.

The speed is decreasing, responding to speed limit advised by end of the footage?

Unfortunately your speed needs to be the 'advised' limit throughout the whole section (assuming it was all within the 30mph stretch).  Eventually slowing the the limit doesn't cut it.

(All assuming any signage does correspond with any TRO)

My understanding was that the penalty is based on them recording 36mph average...

Your understanding is wrong.

Devices measure speed in about a third of a second. You could say it is the average speed over that third of a second but since it is unlikely to vary much during that short period, it is effectively a "spot" measurement.

Average speed systems operate over a longer stretch and work by measuring the time taken to travel between two fixed points, the distance between which is known.

NewJudge, the explanation I received  from JustLoveCars clarified this and was all I needed. I said as much right after the part you took and quoted from my reply. No further help needed. Thank you.