Is the earliest underground colosseum tour at 8:30AM or 9:30AM Rome time?

Is the earliest underground colosseum tour at 8:30AM or 9:30AM Rome time?

I've seen conflicting info for this. Some sources stated the earliest underground colosseum tour is at 8:30AM and some other sources stated it's at 9:30AM (all in Rome time).

I'm going to try to book the earliest tour available for June 15th, and I'm crazy enough to wake up in the middle of the night (I'm in eastern time) to try to snatch this ticket, but I don't want to wake up too early, or worse, wake up too late....

Not sure if anyone will see this in time. it's 10:30PM ET right now. I have my alarm set for 2:25AM ET, assuming the ticket becomes available at 8:30AM Rome time (2:30AM ET)