They're not going to change the release date
This is obviously one of the most eagerly awaited albums in a very long time, so that means everyone will want to get their hands on it and leak it, but it also means the label will make a big effort to prevent leakage as much as they can. The best we can hope for IMO is that it leaks after May 10th.
Lets just assume its only Judas.. lets be surprised if its something else, for all you guys know it can be Judas on piano. No need to try and figure out what other song she sang