This is a minor release with changes and enhancements relating to Skyline cluster.
If you are not running a Skyline cluster then you can skip v3.0.4 and stay on v3.0.3
See release and update notes - https://earthgecko-skyline.readthedocs.io/en/latest/releases/3_0_4.html or
https://github.com/earthgecko/skyline/blob/master/docs/releases/3_0_4.rst
What's Changed
Full Changelog: v3.0.3...v3.0.4