“The first movie she [JK Rowling] sat me down and she basically told me about my whole arc. But then I checked in with her again at the beginning of the second one, she’s like, “Oh, that’s all changed.” I was like, “Oh, man. Come on.” Now I’m at the point where I really don’t want to know what is ahead. I feel like it should be a surprise. I know a little bit of what’s going on in the next movie, that’s all I really need to know.
She’s told me how I make my introduction into the next one.”
Source: Collider