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packages get branched on 8 April. When this happens, does that mean it's possible and/or standard practice to change repository location(s) in yum and continue to update packages, or do the snapshots, preview and final releases each require a total reinstall? Sorry for being so naive..!

(snip)

When the final release comes around we update the fedora-release package to change your default repos to point at the newly-created stable repositories for F9.

So, if you install the Beta and keep applying updates, it will magically evolve into F9 final without any intervention needed[1].

What a relief! I did hope this was the case. Thanks for your extremely quick and informative answers.

Steve