How to install Ubuntu 18.04 LTS Bionic Beaver

sudo sed -i 's/artful/bionic/g' /etc/apt/sources.list
sudo sed -i 's/artful/bionic/g' /usr/share/python-apt/templates/Ubuntu.info
sudo apt-get update
sudo apt-get upgrade
sudo reboot

Source:https://ubuntuforums.org/showthread.php?t=2375562
 

raony