I’m definitely appealing, but was wondering how likely they’ll accept the appeal.
All London councils ruthlessly game the system to maximise cash flow, so reject virtually
all informal challenges with a Fob-Off letter. They do this because they know that most people then cough-up the discount. So submit reps based on your narrative, but don't be disheartened when you get the inevitable rejection.
The basis for parking and paying, is that time is allowed to park and then pay to park. If this wasn't so, then no motorists could ever park legally in a car park ! Your five minutes seems quite reasonable. Newham are one of the worst London councils, being ruthless, venal, and rapacious. I would take them all the way on this PCN, but lets see the PCN first