In our case we weren't even asking for money back or a stateroom credit. I was trying to explain to the CM that we pay more for cruises that don't go to Mexico (a personal choice that we feel very strongly about), and now, in spite of paying more, we're still ending up there...twice. That's when the CM told me western sailings are more expensive. Sure, there may be some based on dates and holidays that are more than others but generally speaking, we have always paid more for eastern than the western sailings around the same dates would have cost us.
What we were asking for was to switch to a different cruise that week that was not going to Mexico without paying a huge penalty. It would have cost us almost $3,000 more to switch to a B2B on the Dream that week because the prices increased significantly before they announced our itinerary change. We were willing to pay more but not THAT much more. We asked if they could honor pricing from an earlier, pre-hurricane date (we booked 1.5 years in advance) and they said no. They were pretty unwilling to work with us on this and other issues that came up as a result of this changed itinerary. They wouldn't even take responsibility for the things that were in their control (lack of communication, switching the brunch we stayed up until midnight to book, canceling the excursion we stayed up a second time until midnight to book, etc.) They just blamed everything on the hurricanes. So, unless you have much better luck than I did, I wouldn't expect a thing.