They would tie up to a new spot every 1.5-2 hours starting at 7am. Second to last dive would be dusk dive, last dive would be the same site for night dive.
Dives were 60-80' on 32-33% nitrox. My buddy usually limited me to around 45 min, so an hour SI would off gas enough to clear for the next dive. I was the only diver to make every dive and it was very exhausting, but completely worth it.
As Wookie said, very self-sufficient diving. It was one of my first dive trips and it spoiled me. I dove with a typical 'follow the dm' on a later trip to Tobago and hated the format, but it was amazing diving there.