If you get there at 8 (early opening or Akershus reservation that someone sits out on) you will have an hour to wait.
If you get there at 9 you will be behind everyone who got there before 9.
Much later, and you run the risk of at least a 2 hour wait.
The thing to do is to get there the soonest you can and if you absolutely have to get in line until later in the day, check and see how long the wait is when you get there.
Im still fascinated by those who make the 8 AM Akershus reservation and then take the $10 per person fee and just go get in line for A&E.