I might add a couple of comments:
On the Seaview Drive look for the Heritage Beach site just east of the Frank Sound Dock. I have bumped into the local guide there several times. The guide likes the water from the Beach site parking west toward the Frank Sound Dock. The Dock is interesting and often you can see muddy areas from the doc where the bones are mudding.
I had my best bone fishing this past spring at Rum Point on the north side. You said you were staying at "the beach" which I assume is 7-Mile Beach. I have never fished the open water there but I imagine its much like the US East Coast. Probably early morning is best. This spring there was a school of about 75 bones
that liked to hang in the roped off swimming area (Rum Point). I got called down once or twice for fishing too close to the area. At the Rum point beach there is a large long flat to the west and if the party boats aren't too thick there are often a lot of fish moving there. This bottom is hard sand - easy walking. Around to the east (go behind the condo till you can get to the water) I have caught blue runners, yellow tails, cuda, snook. The shore line (east side) has a lot of that Ironshore Limestone and is pretty rough wading.
If you get trapped downtown and have a 4 pc (6 pc is better) rod there is a place by the Lobster Pot restaurant (I think it's called Hammond Beach) where the locals clean their catch and there are always some fairly large tarpon there along with cuda. Its a working doc but if all the dive boats are away from the dock no one cares. A spinning rod could
be better here. Easy walk form the main downtown shopping my wife likes and if you are on 7 mile beach it may not be far from there. Borrow a bike. Be sure to visit the Guy Harvey store and have a drink on his restaurant deck.
I find tides in Cayman strange. They don't cycle like the east coast. Maybe someone on the list can explain them.
Pictures are bones in the Rum Point swimming area. I had to wait for them to get under that rope. Caught quite a few. Fly didn't seem to matter but they didn't like the fly landing on their heads even in several feet of water. Take some typical flies with a weed guard as there always seems to be some floating turtle grass
around.