The Hydra gem
Our ability to provide documentation, support and training is limited and so the Hydra Gem was/is, in essence, a technical fix for this. It offers a stable gemset which accepts patch updates but not feature releases and we have promised a documented (not automated) upgrade path to its next major release.
A move from one major release of the Hydra Gem to the next (6 to 7, currently) will have major peer impact and should not be undertaken lightly. There should be release candidates which can be tested in the community with testers feeding back into the upgrade documentation. In order to keep training up to date we will need to accommodate minor releases to the Hydra gem (6.1, 6.2 etc) and these should likewise be tested against the new major release (7.0).
Solution bundles (and, ultimately, any turnkeys from them) should be pegged to Hydra gems, not specific versions of HydraHead, Active Fedora etc.
The release of minor upgrades to the gem and documentation is currently driven by training needs; major upgrades might usefully be pegged to a Hydra meeting where updating the documentation and training documents could kick off.
The process is evolving as we go but seems to be serving us well.