Hi @alexdryden we did a poor job of communicating with open source users about the Fitzgerald deprecation. Typically we try to announce on the forum any planned deprecations well in advance (see Planned Deprecation Notice: Pressbooks LTI Provider Plugin for an example). In this case, we retired and removed several old themes when we migrated the old pressbooks.com multisite to pressbooks.pub. Nearly all of them were private themes, but Fitzgerald was public. Sorry about that.
Basically, Fitzgerald will continue to work as it does now for the forseeable future, but we’re not going to be maintaining or cutting future releases for it. If you want to take over maintenance for it, you’re more than welcome to fork it, but we’re considering it archived on our side.
With our releases, we try to use semantic versioning principles: https://semver.org/ (Ned and Dac did a nice job of laying out our aspirations a few years ago in this thread: About the name of the versions - #12 by ned – I think we’re still broadly committed to them).
We don’t have any current plans to retire any of the remaining public themes, but will try to do better job of communicating will our user community before making changes in the future!