Juju uses --agent-stream similar to how snap uses --channel.
When you run upgrade-controller, Juju will filter the agents it selects from based on the user's desired level of risk; that's why juju doesn't work it out for itself; it must be a user driven decision.
It does look like there's an issue though in that --agent-stream proposed should not have presented "2.9-beta1.3650" as a choice.
Juju uses --agent-stream similar to how snap uses --channel.
When you run upgrade-controller, Juju will filter the agents it selects from based on the user's desired level of risk; that's why juju doesn't work it out for itself; it must be a user driven decision.
It does look like there's an issue though in that --agent-stream proposed should not have presented "2.9-beta1.3650" as a choice.