I went to BI for about 6 years in a row around late July. There is always something to catch. The coast guard channel is a pretty good place to start and relatively easy place to fish. Will be bass and blues there around first light, and maybe a shot at bonito. Fluke can be caught there all day. I'm not much of a fluke fisherman, but it was pretty automatic if you had a few sandeels or silversides to bounce off the bottom.
Never really fished around the jetty at the entrance into New Harbor until one day when I snorkeled around there and saw enough big bass and blues to make me get out of the water.
Can't say I know too much about the other parts of the island from shore as I usually fished from a boat
Heres a shot from last summer. Went out there for two nights with the gf. She agreed to let me bring a pole, no waders though! It rained the whole time, save 10 minutes.
Notice the SWE shirt. Free advertising.