NIP Details and Circumstances
What is the name of the Constabulary? -
Date of the offence: - October 2016
Date of the NIP: - 3 days after the offence
Date you received the NIP: - 4 days after the offence
Location of offence (exact location as it appears on the NIP: important): - LONDON ROAD, OUTBOUND, GLOUCESTER, UNITED KINGDOM
Was the NIP addressed to you? - Yes
Was the NIP sent by first class post, second class or recorded delivery? - Not known
If your are not the Registered Keeper, what is your relationship to the vehicle? -
How many current points do you have? - 3
Provide a description of events (if you know what happened) telling us as much about the incident as possible - some things that may seem trivial to you may be important, so don't leave anything out. Please do not post personal details for obvious reasons - I was driving home from work, there was a vehicle behind me. The speed camera flashed and I wasn't sure if it flashed me or the vehicle behind me as don't recall exceeding the speed limit.

NIP Wizard Responses
These were the responses used by the Wizard to arrive at its recommendation:
Have you received a NIP? - Yes
Are you the Registered Keeper of the vehicle concerned (is your name and address on the V5/V5C)? - Yes
Did the first NIP arrive within 14 days? - Yes
Although you are the Registered Keeper, were you also the keeper of the vehicle concerned (the person normally responsible for it) at the time of the alleged offence? - Yes
Were you driving? - Yes
Which country did the alleged offence take place in? - England
- England

NIP Wizard Recommendation
Based on these responses the Wizard suggested that this course of action should be considered:

Generated by the PePiPoo NIP Wizard v3.3.2: Sun, 16 Oct 2016 16:08:54 +0000

Contact the issuing office, ask for photos to assist in identifying the driver. Post them here, but first remove any identifying marks that would point to it being your vehicle.

Gatso camera, single carriageway, so easy to tell who got flashed:

https://www.google.co.uk/maps/@51.8687253,-...3312!8i6656

Alleged speed?

The OP wasn't sure whether it was her or the vehicle behind her that got flashed. I'm struggling to see how the road being a single carriageway has any bearing on that. The fact that she received a NIP suggests that it was probably her, although mistakes do happen, and JFTP has advised her on the best way to check.

We have had posters unsure who was flashed on DCs, or motorways like Liverpool end of M62. Obviously, 2 or 3 cars abreast of each other would easily cause doubt if camera flashed.

On a SC, the driver would (normally) know if they were on the dragon's teeth when flashed, so one would have thought, no doubt.

Obtaining photos as suggested will of course confirm the allegation.

To add, if the car behind was so close as to create confusion over who was flashed, then either it was braking fairly hard, crashed into the OP just after the flash, or they were both speeding.