HOWEVER DO NOT NOT NOT WAIT UNTIL THE LAST MINUTE TO FILE ... if you do then you risk your computer blowing up, the internet going down, the TT system being overwhelmed and/or the IRS not accepting the return timely. Since Friday the IRS has been taking hours (not a few minutes) to accept returns even from paid preparers and the DIY programs can take even longer still. If you owe you must file timely or the penalties will be applied.
If you have a refund then Monday midnight means nothing to you.