Amended returns have to be printed, dated, signed and mailed in.
I would do this and make any payment of additional tax by April 15th to avoid any interest.
It is April 5th today so give IRS another week and then send in the Amended return around April 12 or 13th just to be safe.
As long as it is postmarked April 15th is all that matters with IRS actually, I just don't want to get caught at post office on April 15th.
