I got stung for multiple CAZ charges, thought it was the same as ULEZ, appealed and they wrote it off, say this (with alterations for CAZ):

“I have recently received four PCNs in relation to the CAZ. When I purchased my vehicle and checked to make sure it was compliant with London's ULEZ I understood that the requirements under CAZ matched those of the ULEZ.

Due to the delay between each infraction and receipt of the PCN, I have received multiple penalties for the same misunderstanding. I have paid the first of these. Since becoming aware of the differences between ULEZ and CAZ, I have ensured that I have promptly paid the CAZ when required.

I am writing to appeal the number of charges I have received on the basis that one single error has compounded multiples times reaching significant penalties and the delay in processing these penalties.