Apologies, I was unable to find the answer to these questions from a while back.
I believe I read that there is a catarmaran trip (for around $75) from EPM (or maybe the marina) I think it included retrun trip, food/drinks, maybe a visit to a turtle sanctuary, a little snorkelling.
I seem to recall that they leave you to do your own thing for a few hours and you return to the cat at an agreed time to return to the mainland.
Does this sound familiar, anyone?
T-Minus 9 days :-)