! Congrats on getting the location and date settled, that's always a big step
we booked our photographer over a year in advance; we booked him in October 2014 when our wedding isn't until January 2016. I loved his style do much that I couldn't risk having him already booked and unavailable for our wedding. In hindsight, it helped us in a few ways.
1) we were able to book and sign a contract using his 2014 prices. I've found a few vendors raise their prices by at least 10% each year
2) as a Canadian bride, having paid his $600 deposit back in October actually saved us money since the Canadian dollar was better back then
3) our hotel changed the outside photographer vendor fee in 2015 from $400 to $800. Since we booked him in 2014, the hotel is honouring the old vendor fee! Woohoo
So basically lots of benefit on our end for booking early. Have you chosen a resort? If you have, make sure you factor in the vendor fees if there are any.
Good luck in your search