Yeah I know, didn't have much of a choice that evening however.
What grounds do I have for appeal?
I can't see any viable grounds at the moment, but somebody may see something.
There may also be a "technical" appeal based on council mismanagement of the enforcement process, and nothing to do with the actual alleged contravention. This is governed by the Traffic Management Act 2004, and a set of regulations. Councils must follow what the regulations require them to do, so if they don't the PCN is void as not following what the law and regulations is a 'procedural impropriety'. Trouble is for these sort of appeals is they are dealt with at the adjudicators, and the full PCN penalty is in play, the discount option has gone by then.