My problem is, somewhere along the way the package maintainers changed the pattern for versioning and now I am stuck on an old, 1.0.1 version (latest version on Flathub is 1.1.6).
While I understand the issue was fixed upstream, I am still unable to update. I tried removing currently installed version 1.0.1 and installing said runtime again but it installs yet again in the outdated version 1.0.1. And flatpak remote-info --log also shows that 1.0.1 is the latest one available for installation.
I think the new version was simply not released, yet. I assume this is not intentional & if you create an issue in the GitHub project then a maintainer will fix this issue.
The GitHub repo contains the current state of the manifest. But this has to be build & then uploaded to the actual Flathub repo (see Flatpak Repositories). If this fails for any reason, then an application won’t be published until the issue is fixed by a maintainer.
If you take a look at the history then you’ll see the status of the automatic builds (check marks & crosses). It’s missing for the latest commit, so it most likely never happened. The previous commit does have a check mark but this was a just test build which is not published to the stable Flathub repo (see flathub_default_branch in Build properties on a build details page, e.g. the last stable build).