A 9 month to 12 month turnaround for a retracking isn't outside the realm of possibility. For all intents and purposes you're building a new rollar coaster. The Coaster manufacturer they are going with has to make the new track, ship it to Florida, Disney has to then tear out the orignal track along with any facade that gets in the way of putting new track in, repair the facade, add any new effects ( if that's what they're doing), then finally testing, testing, and more testing if something doesn't work they fix that and go back to more testing. Then after testing the state safety inspection team will come in and run their tests. Everyone one involved wants to make sure that a train dosen't run off the rails and someone gets hurt or worse.