You made a mistake by putting two different years of income on the same tax return, but somehow the IRS accepted your return and is processing it? WAIT for the return to be fully processed. Do not try to change anything on your return now. Sometimes the IRS catches and corrects mistakes. If they do not catch this, then after it has been fully processed, you should amend.
**Disclaimer: Every effort has been made to offer the most correct information possible. The poster disclaims any legal responsibility for the accuracy of the information that is contained in this post.**
