Good afternoon. Last year I did a Form 1120 return that was intended to cover a short period of several months, ending October 31, 2018. Instead, it was filed as a 2018 return for "tax year beginning 10/31/2018, ending 9/30/2018." I have just now caught the error. I am trying to file the return for 11/1/2018 to 10/31/2019, which would be a true "2018" return. However, ProConnect will not let me file this new return because I previously filed a return with year 2018.
To complicate matters, the previously filed return is no longer in ProConnect. So, I am not sure the best way to amend that return or how I go about amended a return when the only amendment is the date that the return covers.