I think we're being really optimistic with time frames here. Look at SDMT construction as an example. Yes, that's not an identical project (should be noted the huge issue of it being an isolated work site) but the timeline should be similar. I don't think this opens till spring 2019 but I'm pessimistic with WDW construction timetables.
I see no evidence to suggest that you aren't correct. They are habitually slow, without any reason or excuse.