If you file now, it will just sit on TurboTax Servers until the IRS starts pulling returns on January 28, 2019, except for a few returns pulled early for testing purposes. If you file now and later discover a mistake, get an additional W-2, 1099, etc. you cannot get the return back to correct it. You'd have to wait and see if it was accepted or rejected after January 28 to know how to proceed. If accepted, then you'd need to wait on any Federal refund (if applicable) to arrive, then file an amended return, which can be a hassle.
