I was using Ubuntu 19.04 and decided to upgrade it to 19.10. I just used the Software Update Tool.
I did not see any errors during the installation. After rebooting I realized that Ubuntu was not upgraded.
I checked software update tool and got an error message:
Not all updates can be installed
After I clicked Partial Upgrade I got another error:
An upgrade from 'eoan' to 'disco' is not supported with this tool.
So how do I finish the upgrade?