On Bazzite, which is based on Fedora Atomic, I can run bazzite-rollback-helper rebase unstable to rebase to the unstable branch with Plasma 6.3.
Fedora Atomic (and other immutable distros) are perfect for this. Fedora Kionite could offer an unstable release of Kionite with the latest KDE Plasma version to which you can rebase. As you said reverting won’t be a problem.