Ok... I'm going to try to make this whole Star Wars opening date thing as simple as possible for people.
Everyone is on the same sheet of music for Anaheim. They are working as hard and as fast as possible to get it opened by the end of the year holiday season in 2018. My sources will go so far as to say that they are hoping for at least soft openings for Thanksgiving next year. So, West Coast opening is pretty clear and baring any huge delays outside of Disney's control (weather or huge technical delays with either Bird or Alcatraz), they are willing to add as many man hours to the project as needed to get it done on time.
The differences in opinions on when WDW is set to open are the variable. Spirit says 2020. Martin thinks 2019 is possible. While I won't speak for them, I'll just say that my sources haven't waivered in 2020. It was 2020 before it got announced and it was 2020 when it did and it's 2020 now. Don't get so caught up in the semantics of if it's going to be "months", "a year", or "years" after Anaheim and keep it simple - it's going to be 2019 or 2020 based on what you read around these parts.
Beyond that - use common sense. As I said above, Anaheim's project is "working as hard and as fast as possible" and they are "willing to add as many man hours to the project as needed" to reach the 2018 holiday season date. Do you think WDW is doing that currently on this or ANY project? Until or unless that changes, there is no way WDW will open SWL months after DLR. It just can't happen. While ultimately it is a question of willpower, the real variable in the equation is manpower. WDW simply doesn't have the will to pay for accelerating this project by giving it more resources to move faster. That doesn't mean they can't have a change of heart; but, if they do - the proof will be in the pudding of seeing WDW's construction sites look like Anaheim's (and more if they are going to catch up).
I can't speak for TDO; but, my opinion is that in their eyes - they have enough in their pipeline to keep the rubes coming back for more until it does open. Pandora and Toy Story and Rivers of Light (haha) and some things that haven't been announced. Do I think that's the right choice? No way. The resort is stuck in the swamp literally and figuratively. They have rested for so long and maintained such an operating margin that it's hard to fault them for not changing. An object at rest tends to remain at rest.
I love Disney Parks and I love what WDW was and I dream of what it could be in the future; but, I don't pretend that they are close to delivering today on the promise of what their legacy has historically shown is possible. If "Spirited Change" is ever going to come... they can start proving it by putting their foot on the gas pedal by opening up those pocket books even more.
*And yes, they are starting to spend money at levels greater than we seen under Emperor Iger's reign; but, that doesn't offset more than a decade of neglect and it doesn't change the truth that Parks can't continue to do their old math of DLR =1 and WDW = 1 when it comes to dividing up the capital that actually makes its way into the theme parks. DLR has 2 hungry mouths to feed and WDW has 4 and the east coast kids are malnourished.
**Oh, and as a completely unassociated aside (since this thread is most definitely the place for it) - make every effort to head to the theaters to see La La Land. It will warm your heart and put a smile on your face. Which is much more than we can say for the usual doom and gloom we get around these parts.