Recently I was updating from Ubuntu 14.04 to 16.04 from terminal. After starting the update, I accidentally closed the terminal process running it. It was the initial stage of the upgrade process and the required packages were being downloaded.
After this, when I opened the software updater, it was prompting for a partial upgrade. From my little knowledge, what I could make out was that the /etc/apt/sources.list was pointing to the new release which is Xenial. So I replaced the sources file with the sources.bak file available in the same location.
Everything looks alright now. But when I again try to upgrade using sudo do-release-upgrade, it is showing No new release found.
What can I do to fix the issue and make the upgrade work?