If you have a rigged up DeLorean all you have to do is hit the right speed and you are in luck.  If you don't have one of those, just hope it rejects.  If not, sounds like you will have an amended return to prepare.

You can't.   Hope for a rejection, otherwise you'll be amending.

And that speed would be?  Don't Google it !

I didn't think speed was relevant.  All the Doc needed to do was to set the date.  So, I'd think that the OP can go back and undo the e-filing without monkeying with the speed, which should theoretically be set automatically, if he/she has got the correct date (provided getting access to the DeLorean is not a problem).