At our company we do 3D BIM construction projects (schools, hospitals, high rises and such). BIM is "building information management", it allows for clash detection and building trades coordination. Once the MEP portion is completed, Mechanical, Electrical and Plumbing, the rest can really go quite quickly. When the building was constructed the industry was not really doing three dimensional modeling. I would wager three FP(s) that the mouse created a 3D model of the structure and designed the rooms in virtual 3D space. This would allow them to prefab a lot of stuff, (water mains, conduit runs, fixture locations, etc.) It seems like everything would be ordered and delivered so that the finish work snap into place like a jigsaw puzzle. Based on what Dean said they are doing the MEP right now. Christmas time might be doable to have occupancy, at least on some floors in the south wing.
I downloaded the permit drawings last year when the news broke about the expansion. There is a lot of six and eight inch underground piping for the the cabins, pool and the buildings at the pool area. Perhaps I am wrong, but judging by the pictures I have seen online, no UG pipe work has even started. To do all of that trenching and pipe, pour a concrete pool and surrounding deck, build twenty-four (? or more) cabins and all the associated infrastructure (walkways, landscaping, lighting, pool fence, etc.) by mid 2017 seems like a very heavy lift. Project completion would be much closer to 2018. IMHO. Just saying. Plus how long to recreate the Mickey topiary?