Sorry to burst your bubble, but you haven't been approved. ATF recieves the paperwork, then deposits the check automatically. Usually it shows up cashed in 1-2 weeks. The app then sits in the pile on the inspectors desk until they get around to it. The wait time from check cashing to tax stamp was around 2 months, but my guess is that got extended after the election. So you are looking at mid-Feb or later before you get your stamp if history is a guide. Look at the bright side, it gives you more time to get your parts together.