Best not to freeze the wine. Depending on the alcohol percent the freezing point is somewhere around 20-25 °F. So best to keep it at around 25-30 degrees. If crystals start to form right away, a few days to a week is long enough. If you find the crystals forming slowly or not forming - you can add some seed crystals from a previous batch or just sprinkle in a tiny bit of cream of tartar to start crystallization.