Honestly, i'm 100% convinced it's Cece now, it just seems so obvious
Marlene said on twitter a couple of days ago that we've seen Big A in a black hoody, so far we've seen Cece be revealed; as Red Coat, a Black Hoody and the White Coat at the ball, she's been nearly every reveal
and
if she thought she was Ali and the first thing (the only thing that we saw) she said to her was
"I did everything you told me to do"
Which at that point would have been Alisons advice on being cool, which she followed
Mona told everything to Cece when she was in radley which is how A knows everything, when she came back to Rosewood at xmas Alison filled her in on everything that was going on, which, once again is how A is one step ahead
Cece has the motive, the resources, the knowledge and Grunwald even said something about Alison being betrayed by someone close to her, who else but her supposed best friend that she confides everything in?
