Luton Airport APCOA PCN - picking up on slip road

[Tigerpoo]

Hi there.* I'm considering sending an appeal to POPLA as my internal appeal to APCOA failed. I have already admitted that I was the driver of the vehicle so does this reduce my chances of success? I gather mitigating circumstances are not taken into consideration so I feel I only have the stopping not parking, lack of contract between me and them as I was not in their car park but on the slip road, inadequate signage for dark wet weather and confusion from them on PCN on the one hand and stopping/dropping off stated as the reason for a PCN. I don't fully understand the POFA and bylaw thing and if I am the owner and driver perhaps I can't use that anyway?
Grateful for advice and whether my case stands a chance with POPLA.
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