We are planning for Sept, 2017. I typically start planning a year to a year and a half in advance. I find half the fun is in planning. I have a notebook half filled already as we are debating between two resorts, and trying to narrow down dining. We generally have a 3-4 year gap between Disney vacations (we like to travel to other places in between) So starting planning early is a must as I need to get caught up on all the changes.