Hello!
Congratulations! You can advise them that you want the beds configured into a King in advance, however at this late date it might be difficult to do. Chances are it'll be that way when you board anyway, and if it isn't, just let your cabin steward know that you'd prefer it that way, and he'll fix you right up.
What ship are you sailing? The lovely Mrs. Jones (Vita) and I are sailing the Glory on Aug. 5th. If that's your ship, we'll look for you!
Ken