The introduction of a new version for a [compat] listed package results in nonempty status --outdated often enough that a safe opt-in way of reducing these events is desirable.
To ensure the processing happen only if the package owner[s] want it (to prevent the processing otherwise) consider an .github/workflow/autocompat.toml that at its most simple would “know” when a [compat] listed package has merged a new version which is not covered by the current Project.toml.
In that case, a temporary branch is created and the only changes are to the Project.toml (a) bumping the owned package’s version patch number (b) extending that package’s [compat] string to include the new version number (in an intelligent way, to prevent accumulating too many too specific versions)
Then run the owned pkg’s tests on this branch using the new version of the [compat] package. If the tests pass, then merging the change into the main branch with an appropriate comment and register the update.
Within the .toml file, finer control would be available. For example, selecting which external pkgs are “active” in this way (if not all [compat] entries) or providing a waiting time before a new version of some/all [compat] pkgs are processed.
