You should have been asked, when you e-filed your return, to select a date you'd wish to have your account debited for the tax liability to the IRS.
If you fail to select a date, the default date is the tax filing deadline. For 2017, that date is 4/17/2018.
*** I am NOT a tax expert. I am a seasoned TurboTax user, and volunteer to provide assistance to TT users. Nothing I post is to be considered TAX ADVICE; I bear no legal liability for responses.***
