No doubt you only became aware of the contravention when the first PCN arrived followed by three more, correct ?
In cases like this, it has previously been successfully argued at adjudicators that not knowing a contravention was being committed until the first of several PCNs arrived, means a disproportionate and excessive penalty is being demanded. In most cases the adjudicators rule that the first PCN being paid and the others cancelled.
Your case is stronger if you can show your use of the website mislead you. As Birmingham haven't re-offered the discount you must now take them to adjudication, (the Traffic Penalty Tribunal), because it is pointless paying-up until an adjudicator has looked at your case, as the penalty remains the same with no additional costs.
Actually so far I've only received 3, I am saying 4 because two cars were being driven at the same time, so it's probably just a matter of time I receive the fourth one.
I had no idea this was going to happen and I really help they can cancel it but my concern is that the adjudicator might say pay the first for each car, which is still a substantial amount.
Do I have to wait for something or can I appeal to an adjudicator? also can I make a single appeal giving the reference of the 3 PCNs and information about the missing one?
Is the address you checked correct? 80 Bordesley Street, Birmingham, West Midlands, B5 5QH
The Royal Mail postcode checker, which should be authoritive, says the B5 5QH is for addresses on Pickford Street.
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There's no argument about whether the vehicle is compliant or not. As I've explained earlier, I knew our vehicles were not compliant because we pay for ULEZ when we go to London so I checked for Birmingham too and it wasn't compliant. I would have paid the charge right away had I seen my destination being within CAZ, it's a no brainer paying £16 for 2 days fo each car instead of £120 for each car (even more now) but I was mislead by the website.
I agree with your points about it being the driver responsibility to make sure their vehicle is compliant or not.
What begs the question is why in situations like these, the same burden doesn't fall on the council.
Cities now have parking, street, CAZ, and all other kind of restrictions; if as an outsider, I have to check the map provided by them, then cross check it with the Royal postcode checker and also manually zoom in to triple check if the destination is within CAZ then I might as well walk around with a paper map.
Also I was checking google maps to understand how these CAZ sign post look like and I was shocked to see that some of these are on the side of the road on an average height pole. How does one spot them if, for example, a lorry is driving in front of them?