So it's a rental:
You therefore must contact the hire company to confirm to them that you intend to contest the PCN, and tell them that when they receive the notice to owner they must transfer liability to you. If the hire company is stupid (as many are) and just pays the PCN, you lose the right to appeal.
One of the best arguments will only work at the notice to owner stage, but it is of crucial importance that you must not send the screenshot to the council with the informal representations, as we can adopt a variation of the strategy explained here.
Basically once you have the notice to owner in your own name, you send the council a representation with a link with a click counter that redirects to
https://imgur.com/a/412YLHO and then if they don't open it, we've got them on a procedural impropriety.
The other issues is putting them to proof as to the signage, there are no signs in the bays telling you it's an event day, they rely on the zone boundary signs. I found one
here, but where exactly did you enter the zone?
You'll need to look up the TED zone on the map here
https://new.haringey.gov.uk/parking/cpzs/map-haringey-controlled-parking-zones-cpzs and work out exactly where you crossed the boundary. I can then find out if the council can prove what signs were displayed on the day of the alleged contravention.
