This question already has an answer here:

I found CD images for the 18.10 beta, but I'm wondering if there is a way to upgrade OTA. I have the bionic-proposed box checked, but there is still nothing.

marked as duplicate by pomsky, karel, muru, dessert, Eric Carvalho Aug 21 at 12:12

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  • Questions related to any version prior to final release is off topic here. – Kulfy Aug 20 at 18:28
  • This is about upgrading 18.04. Border case off topic I would say. But there IS an answer so I took the liberty to answer it. We do need beta testers, don't we? – Rinzwind Aug 20 at 18:34
  • 18.10 is Cosmic, not Bionic. Enabling the bionic-proposed repositories will do something other than you intended. Undo that. – user535733 Aug 20 at 19:03
  • See also the following link, Ubuntu Development version / How to participate – sudodus Aug 20 at 19:44

Pre-requisites:

sudo apt update 
sudo apt upgrade
sudo apt dist-upgrade
sudo apt autoremove

Those will make sure your current system is up to date.

Edit /etc/update-manager/release-upgrades and set Prompt=normal to avoid the "No new release found message."

This will start the upgrade:

sudo do-release-upgrade -d

Big fat warnings:

  • Please do not do this on a production server. 18.10 is not ready for general usage and breaking your system is more likely than having a working system. Every new update might break something.
  • If you have personal data do make a backup every day and save them all. At some point you might need to re-install as every update could break your boot procedure. Knowing a little not more then average about the inner workings of Ubuntu so the base system, Linux, systemd, the boot process would be good to have.
  • Biggest problem probably will be 3rd party drivers. I would remove them and stick to the open source versions when upgrading and re-enable them when there is a working newer system.
  • +1 for the wisely phrased and prominent warning. – user535733 Aug 20 at 19:01
  • @user535733 gonna extend it even more :+ – Rinzwind Aug 20 at 19:04

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