Free Traffic Legal Advice

So just to clarify - at the time of me entering the CAZ, the car would have been showing as non-compliant on the CAZ website checker.
I did not know there was such a website and I assumed that as my car was ULEZ compliant, it would also have been CAZ compliant.

The "miracle" which had happened was me obtaining the relevant documents proving my car was compliant and getting the CAZ admin team (who were very helpful btw) to update their database.
Birmingham council then checked the latest database and dropped the charges. I doubt they have the tech know how to get a backdated version of the CAZ database 

So to update and close out this thread: Birmingham city council rejected my representations (no surprise really) so I appealed to the traffic penalty tribunal and they cleared all my PCNs, hooray!

For anyone in a similar predicament, the process was:
- Obtain a certificate of conformity from the manufacturer (took 4 weeks)
- Send in a copy of the CoC along with the V5C to the DVLA so they could update the emissions details (took 4 weeks)
- Fill in a form on the CAZ website and upload a scan of the V5C (updated instantly!)

Thanks for everyone's help and input, there were actually 4 PCNs in the end which would have added up to a painful amount!
And lesson learned - never assume government databases are consistent with each other. Just because a car is ULEZ compliant does not mean it's CAZ compliant and vice versa.

Hello, thanks for posting this. I am in a similar situation with Birmingham CAZ. I have contacted their customer support and explained them about how my vehicle is ULEZ compliant and it should be CAZ compliant as well. They said it will take upto 15 days for their customer support team to give me a proper advise. I received one PCN yesterday and am expecting more since I entered the CAZ multiple times.
May I know were you charged for requesting a CoC from car manufacturer?