In my past experience with Carnival, they usually put the two twins together to make a queen/king arrangement but the beds are still made up as twins. Is this the case on the Legend? I always take an egg-crate mattress because of a sore hip (I'm miserable on hard beds). Anyway, I need to know if I should take 2 twins or 1 queen/king. (My husband thinks he should get one, too!) It makes a huge difference in comfort but I don't want to have to cut one in half if I can help it.
I was on the Legend last New Year's and I do believe it had the same bed setup as my other two Carnival Cruises - Triumph and Victory, which is the way you have had it before with two twin beds. However, I am NOT positive. I am 90% sure, but more than a few cruises, they all mix together. I hope this helps, not sure if it does.
Just ask them to put the beds together and to use King size sheets and blankets. They also have an insert that eliminates the crack between the beds. I don't know if you call it a Filler, but they should know what you mean. We did this last cruise which was on the Legend.