Interesting. Saw this listed under 4 person rooms for Jamaica...

ISG Inside Stateroom (Guaranteed Rate)
Purchasing a stateroom in this category guarantees an Inside Stateroom rate. Room assignments will be done at the discretion of S.S. Coachella; you will not be advised of your actual room number until approximately 30 days before sailing.
Price listed is per-person based on double occupancy (not including fees). $700.00
Same with Bahamas, except for $500.