This should be used wherever we need to show the latest release
date.
Don't use this in the release notes however, as it will be easy to
forget to update it when adding notes for a new release.
Use &repmgrversion; entity to generate the current version number and
prevent document bitrot.
Also define a "release-current" ID attribute for ease of linking to
the current release notes.
Per notification from the mailing list.
