You changed your mind, and want to e-file your tax
return(s) instead of printing and mailing. As long as you haven't already
mailed your 2017 paper return, you can switch to the e-filing method (through
October 15, 2018). Some states now require e-filing their returns, and federal
and state returns must be e-filed together.
For more information see the TurboTax FAQ below:
https://ttlc.intuit.com/replies/5561257