> Also any chance they'll let me in with a tiny camping stool
Unlikely. Security would probably take it off you.
> wondered what time to turn up?
That depends on whether you have a standard ticket or paid the extra for VIP. I went last year to Green Day and turned up about an hour before doors were supposed to open and the standard queues were already at least an hour long.
Maybe have a cheap folding stool for the queue and abandon it when you get to security. |