No Bootable Device found

[FrenchPress]

There will be an upgrade path later this year.
But you have to wait.

[DEFUNCT] Perform do-release-upgrade / Direct Upgrade on Zorin OS

Update as of July 2023: The Zorin OS Direct Upgrade (do-release-upgrade) path is now released rendering the following thread a piece of archived history. For the Current Guide, please see here: The commentary below remains for the record and the thread is now closed. Zorin Group company has announced that they are working on a Direct Upgrade path (the do-release-upgrade command) for a major Zorin OS release to the next major release. These are not 'point-releases' but are moving for examp…