TurboTax not allowing amended return to be e-filed ?

I have to file an amended return (W-2 was corrected after I'd filed). I e-filed both state and federal returns successfully.  TurboTax is letting me e-file my amended state return, but not the amended federal return - and no explanation as to why.  The help page on amended returns suggests that I should be able to e-file the 1040x as long as the original return was e-filed successfully.

 

I really don't want to print out 30+ pages (I like trees...).  Is there any chance it will change in the future?  Perhaps after the Apr 15 flurry dies down ?

 

thanks!