That whole confusing Phase 1, Phase 2, ....,Phase 4. Is now more like Phase 1.1, 1.2, 1.3, Phase 2. It was originally planned to be as one project was wrapping up, the next would start with about a 6 month overlap. That was to keep as much stuff open while still building. But that was a six year plan and operations had a hissy fit. Now, the phase one projects will all be started by the holidays of 2016. Huge swaths of the park will be inaccessible and what is open will be construction walls as far as the eye can see.
The good thing is the timeline has been significant compressed and we will get the joy of seeing Disney "BUILD LIKE YOU MEAN IT!"©. By Christmas 2018, DHS will be beginning to resemble a world class theme park.