I would plan as soon as you can for New Zealand as November is the start of peak season. This will give you the best options for price and availability. You can start a year in advance, but since flights are not available until 11 months prior, you can wait until January and be fine.

I am not sure what you are asking about flights regarding the resorts.

For recommendations on properties, what kind of price range is your budget? That will help get better suggestions for you.