You will not be able to start a new online return after the October 15 deadline. Do not mess with or make any changes to the 2023 return you already prepared and filed or you will damage it permanently. The CD/desktop software could be used for your purpose but you would have to pay for that download. Why not just wait for the 2024 software to become available later in the year...
**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.**