How far in advance does Carnival post itineraries?

[loudsilence99]

So I attempted to google this and couldn't find anything (well... not on the first page of results anyway :D )

 

DH and I are planning to take our first cruise this November for our anniversary: a 4-nighter Bahamas sailing. The cruise line and ship are still TBD. Why? We're trying to think ahead. Carnival is currently our top contender for a variety of reasons but we're still considering.

 

We are planning a grand vacation for June/July 2018 in celebration of my anticipated graduation from grad school. I have dreams of a Southern/Eastern Caribbean itinerary. We would like to be able to book this sailing on board to save money/reap the rewards of onboard bookings. And, you know, to have two years to pay for this vacation.

 

And so I circle back to the original questions: how far in advance does Carnival post itineraries? Will Carnival have posted their summer 2018 plans in time for our November 2016 sailing?