This thread is FULL of platinum experiences, did you even bother to read? Only the last page is already answering you questions. All IMHO
Anyway, in short: I stayed twice over the past 3 years (both paid stays). Don't expect an upgrade, apart from enhanced view/location. During lower season you might get an upgrade (from tropical villa to seaview villa in our case), during high season one of the better located villa's (seaview villa booked and got the one to the right of Z-bar with great views).
Great happy hour at Z-bar for plats.
Early check in and late check out: entirely depending on occupation.
Full breakfast.
It's a great hotel, enjoy!