With regards to dates, the NtK complies with section 9(5). It is dated Friday 10/05/2024. It requires two working days to be “deemed” as “given”. Therefore, irrespective of the actual date you received it, it was “given” on Tuesday 14th May, one day before the deadline. Unless you can prove it was received after that date, that argument has no legs.
Do not despair. The NtK fails the strict requirements of PoFA 9(2)(e)(i) to invite the keeper to pay the charge. So, no revealing the identity of the driver. Any appeal is made only as the keeper. They have no idea who the driver is unless you tell them, inadvertently or otherwise.
There are always issues with ECP signs. They have lost at POPLA many times over their poor signage as long as this is clearly highlighted to the assessor with identification of which part of the BPA CoP they fail.
Can you get some photos of the signs at the location with a general overview of the different sections of the car park that you say have different terms?