Depends...
As you may know, the sun goes around the earth (I believe the elephants push it along or something - a bit technical for me), so you get different light falling on different things at different times and this is all getting a bit obvious, really.
How long are you there for? If it's a few days, go out at different times, take shots, then do more at other times.
There is no`best` time, not really. You will find different things to photograph at different times.
I'd pitch a tent on the beach so's not to miss anything.