It's being announced that Fox is moving Frankenstein's release to Jan. 16, 2015...which explains why James says in this IGN article they're not starting to film until January:
James McAvoy is about to start work on a new film loosely based on the legend of Frankenstein. Written by(Chronicle) and directed by (Lucky Number Slevin, TV’s Sherlock), the film stars McAvoy as Victor Von Frankenstein, and revolves around his friendship with Igor, who is played by .
And while recently interviewing McAvoy about the really rather brilliant Filth, we also quizzed him about this forthcoming flick.
“We’re shooting in January” he revealed. “We had our first day of rehearsal last week with Jessica Brown Findlay and with Daniel and Paul our director and that was really good, really heartening. Everybody seems alright, so we’ll just see what happens.”
As for how it will compare with previous versions of the story, McAvoy explained: “I don’t think I’ve ever watched a Frankenstein movie. I’ve read the book, but this isn’t based on Mary Shelly’s Frankenstein that much. It’s taken from it, obviously, as inspiration, but it goes on its own path really.
"It’s more of an adventure and the relationship between these two guys – this brotherly relationship that we explore. It’s a really dark adventure – it’s not really an action movie but it’s got a lot of action in it. But it’s really about this relationship that forms the backbone of this adventure that they go on.”