It would be a new PEP bumping the metadata version to 1.4 (that will be less tedious than it used to be though, since it will only have to cover the enhancement, not duplicate all the old field descriptions).

Somwehat related though, we should probably have a summary table in PyPUG mapping metadata versions to minimum required tooling versions & their respective release dates. That way folks can make informed decisions about their installability choices before deciding which version to use in their published metadata.

Cheers,

Nick.