As of today:
11 days until 12-night British Isles on Disney Magic (7)
129 days until 7-night Western Caribbean on Disney Fantasy (8)
215 days until 4-night Bahamas Christmas on Disney Dream (9?, if I can convince the wife)
388 days until 11-night Southern Caribbean on Disney Fantasy (9, possibly 10)
494 days until 4-night Baja on Disney Wonder (10, possibly 11) - back-to-back
498 days until 3-night Baja on Disney Wonder (11, possibly 12) - back-to-back
And the highest number anyone can have right now is 584 days for the 7-night Eastern Caribbean on Disney Fantasy departing December 30th, 2017.