Never underestimate WWE's capacity to screw up a good thing or ignore simple logic for the sake of a swerve, or their obsession with getting heat on the heels. I'm not taking ANYTHING for granted until if/when Becky's hand is raised in victory at Mania and that belt is around her waist.
WWE's track record, isn't very good in this regard (also the last three Mania's have had not great endings either), so I'm not assuming anything. I mean it made all the sense in the world for Booker T to win at Mania 19 given the story, or CM Punk at NOC 2014, or Sasha at HIAC or Roadblock a few year's ago, etc. But it didn't happen in any of those cases.
But I'd be thrilled if I was proven wrong in the end and they did the right thing this time.