When you release the output for a publication, the status of the publication changes to Released.

Tridion Docs automatically changes the output status to Release Candidate when all referenced content for a publication is in released state and no errors or serious warnings occur during the output generation. When the output is in the Release Candidate status, you can release the output. This process archives a record of everything in that publication.

When an output format for a publication version is in Released state, you cannot make changes to the contents or output of that publication. However, you can add additional output formats that use the same contents. To update a released publication, you must create a new version of the publication.