Agree 100% with NCSailor.

And given an 8:30am departure from West end, You'd have to do the boat debrief the night before.

Regarding the first day, I assume you have a noon boarding. So you are more likely to get off the dock by 2pm or so. What kind of boat will you be on? A powercat would certainly be better.

Another option you might want to look at is hiring a Captain. Perhaps with a hired Captain, they could pick you up and drop you off in STT. Or at least drop you off at West End before returning the boat.