This is just a theory that FS3D release date is in October or longer than October for Europe and the U.S. To see why, go to the eshop and then tap the comming soon tab. On the comming soon, all games are listed in order based on release date (well at least i think so) and FS3D is put right behind Pokemon XY which that comes out in October as well. This could be possible or could be changed over time but idk.
tell me what you think about this and/or when you think it may come out in the comments.