Comment 21 for bug 2008509

Some follow-up items:
- This needs to be committed to main also (not just 2.9) and all other supported releases (3.x)

- This hopefully also fixes the other series-upgrade bug where it doesn't get the correct charm build but needs confirmation: https://bugs.launchpad.net/juju/+bug/2008248

- We really need a workaround to get out of this state once it happens. Currently we have no way other than removing the unit which is not great in a production scenario - replacing a unit should be easy in theory but in practice is problematic for many reasons - so a workaround to get out of this state would be very helpful for support

- Peter: The OpenStack & other documentation needs a warning that you must upgrade to a fixed version with emphasis :) I would say in general make it a hard requirement to install the latest point release of a supported juju version, regardless of this bug.

Is it too late to get this into 2.9.44? The release status is not totally clear - it has some milestone bugs still tagged in progress currently.