parking for no longer than a minute
Sorry, but this stretches credulity. The CEO had time in his absence to check if the car had a parking session recorded, then enter the details of a PCN, and probably take some photos, serve the PCN to the car and walk away. A lot longer than one minute, surely. Basically, your friend chanced his arm that a CEO would not turn up and lost. There is no requirement for any observation time in law.
London councils now flood the streets with CEO patrols 24x7 because it makes them so much money. The only possible hope is that there is an appeal argument based on Islington mismanagement of the enforcement process. There have been successful appeals at London Tribunals on this recently, but I'm not the expert, so wait and see if others come up with anything. The only downside is that it involves going to London Tribunals with the full PCN penalty in play. There is no discount option at adjudication.
