GitHub Contianer Registry for GHES?

Is there a roadmap for adding GitHub Container Registry to GHES? The current docs for using Docker with GitHub Packages states:

Note: The GitHub Packages Docker registry will be superseded in a future GitHub Enterprise Server release with the Container registry, which offers improved container support.

The only entry in github/roadmap is #90, which has a similar statement:

note: we plan to replace the Docker service with a beta of the GitHub Container Registry in the next GHES release

What does “next GHES release” mean? Package support came with GHES 3.0, and there’s been two point releases since then, with 3.3 in RC now. Is this waiting for GHES 4?

Not having the container registry means that Docker buildx, and by extension, docker/build-push-action@v2, don’t work on GHES.