I’ve had 2 retrievals at 10:15am and 1 at 3:15pm. You arrive 90 minutes ahead of your retrieval time and plan to be there for about 4 hours.
A receptionist told me that SGF likes to fill in time slots of their appointments (other than the monitoring ones) in chronological order. My guess is it’s the same for the retrievals too. I was the last patient on a Friday monitoring appointment, which ended up being the day of my trigger shot. On Sunday, my retrieval was at 3:15pm and I was again the last patient. My guess is if you’re trying to aim for a later time, don’t have your monitoring appointments first thing in the morning around days when you think they will trigger you.