The multiple-series-charm support has been added in Juju 2.0 specifically to enable upgrades of services in future. The idea is that a charm supports a window of series, and operators can upgrade the underlying hosts smoothly. We don't have quite all the pieces in place yet but its close.
In general I would say move to charms that support trusty+xenial, or just xenial. Mark -- Juju mailing list [email protected] Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/juju
