You can always file it now and your return will be ready for them the second they start processing these held returns. They may even start sooner, so best to be in line!
NOTE: Any returns that include
Earned Income Credit and/or Additional Child Tax Credit will also be held
until around mid-February. And refunds from those returns will start releasing
in late February.
From
<https://ttlc.intuit.com/questions/4158238-why-did-i-get-an-email-saying-my-documents-were-ready-but-...>
[edited 2.1.2018, 12:30pm]