What I am wondering, is if juju takes the series a charm can run on into account.
With this I mean, if e.g. trusty is removed from a charm and a new version is uploaded (without trusty support) and on a trusty cloud I do a new installation of that charm, will juju then automatically pick the latest version that had trusty support, or do I need to explicitly tell it which version to use.
The same / similar question for this, is the scenario in which I run a juju upgrade-charm on a trusty cloud when some of the charms dropped trusty support. Will this result in error / failure messages, or will juju consider the fact that there are no new updates available with trusty support.