Yes, at CSS the advanced morning dive is at 9:00. Not sure about the beginner p.m. dive, but probably the same, around 1:30. My husband goes every morning & enjoys it. He likes the Ocho Rios side diving better than the Negril side. Don't know more details since I don't dive !! He actually got certified at Sans Souci way back in Jan 2001 (by Michael who is still there).
When we were there last April, we went out at 9am for the deep dive then came back to the resort for about a half hour to an hour. We stayed in our wetsuits, rinsed off in the shower on the beach then went and sat at the pool bar with a blended cranberry - pineapple juice, mmmm good. We went out again by 11am (ish) for the shallow dive. The reason for the time difference is due to the size of the resort and the number of divers. CSS tends to have fewer divers and fewer resort courses, so they upped the later dive to get us all back to the resort as soon as possible to maximize our free time.