I did the first one, and I felt like a kid on her first day at school. But it was pretty simple.
Roads were not closed, but I saw very few cars, quiet 'country' roads at Elimbah.
Plenty of people on their trainers warming up.
Most were in a club kit.
A few days before the race, they'll put out a start list with your start time (in 30second intervals). Turn up, sign in, get your jersey number and bike transponder and zip ties to attach to your bike. They do bike checks to see if your bike is compliant or not. Someone will hold you at the start. Go for your life.