Except your "IF" in this is not about who's gonna master the album (that has been confirmed) but about who he is.. Either way, you are getting mad about it months before the release of the album..
Anways, as someone else mentioned before, there are many factors that make the sounding of an album, not just the guy that's doing the mastering..
And, besides this, I personally don't have any "reservations" at all about things I'm so impatiently waiting for, nor think everyone would immediately do something like that based on poor evidence.. I just don't see the point of doing that..