The Form 1040 should be available to file by mail on 01/02/2020 after noon Pacific time, subject to change. The Form 1040 for e-filing should be available on 01/03/2020 after noon Pacific time, subject to change.
See this TurboTax support FAQ for an Advance on a 2019 tax refund - https://ttlc.intuit.com/community/refunds/help/about-refund-advance/01/27333
