> Metacello supports both, but not at the same time. Either you mark your configuration with fixed versions (best for patches) or with symbolic versions (best for releases).
I don't understand this. If you don't want your dependencies upgraded, you don't change the versions referenced in your new version, if you do, you manually change them. Either way, you make a new version, whether it's a patch, enhancement, or total overhaul.
The symbolic versions, OTOH, map your versions to their status on respective platforms. You would do this for every new version.