Hi 3 timer!
They never contacted us. We received a letter after our deposit giving us a number to call within 60 days prior and 2 days before sailing.
I called on that day and reserved our Dolphin Encounter in Nassau. Since this was a 4 day, I left all other ressies for when we got there.
We checked in to a resort before since we had land/sea package. At our resort we were given a letter to meet Concierge between a certain time to book ressies on the ship and get the kids signed up for their clubs. It was very easy!
I have a trip report posted on the other board that describes our Cat3 services in more detail.
We rebooked Cat3 for a 7 day! That way we'll be able to enjoy it more!
Ask any questions you'd like!