You can book a room-only reservation up to 499 days in advance, but you would have to call and they would charge you for the first night, but at the highest current rate, which they would then adjust when next year's prices are released. The prices for next year are released in the summer (typically August, but I think it was June last year), at which time you can book both room-only and packages online. If you want to buy tickets separately you can buy them anytime because unused tickets never expire.