After you file

<a rel="nofollow" target="_blank" href="https://www.irs.gov/newsroom/to-help-taxpayers-irs-clarifies-some-common-early-filing-season-myths">...>
The IRS is supposed to make more info available on Feb 17.
<a rel="nofollow" target="_blank" href="https://www.irs.gov/pub/irs-pdf/p2043en.pdf">https://www.irs.gov/pub/irs-pdf/p2043en.pdf</a>