Sorry, don't think he's a coatie. Normally a coatie will at least have noticeable extra ear, paw, chest fluff.
I've got a coatie. These are pictures of him at 8 weeks, 3 months, and 9 months. Even at the awkward stage, he still had the extra floofs around his ears and chest.
You still have a gorgeous pup there, love that handsome face!