Previous guests have advised that they will normally make reservations for the first day or two.  As you said it is high occupancy season so flexibility is the key.

Mike

When I was there in May I made dinner reservations ahead of time for our night of arrival. It wasn't a super-busy time (I think they said occupancy was 60-70%). I don't know if they would do the whole stay for you. We were flexible about where we ate w...

My wife and I will be at the Grand in early January and I was wondering about dinner reservations. Can they be made in advance of arrival? Is this a good idea during the busy season? My wife does NOT like a late dinner, so I am trying not to disappoint...

I have heard that rollaways are available at IB Cozumel but I have never seen them.
There are no bathtubs and no room service.
You can contact the hotel directly at   rpcozumel@iberostar.com.mx

Try these links:

http://www.cancuntravel.com/tulum-express.asp
http://www.destination-store.com/tour/cancun/tulumexpresstour/
http://www.cancunvista.com/travel/tulum_express.htm
http://www.fantasytravelexperts.com/tulum_expres.shtml
http://www.cancunti...