Preview Campaigns have been placed there by Jornaya for the purpose of testing new Jornaya campaign script releases.
When Jornaya alters its campign script for a release, the new code will be pushed to all Preview Campaigns prior to being pushed to all production campaigns. The purpose of pushing to Preview Campaigns first is so creators can test the new script in their development environments to ensure that no new features in the release will negatively affect their webpages.
Creators can expect an email informing them when a new release has been pushed to their Preview Campaigns and that the testing window is open.
To test a Preview Campaign, creators should implement the Preview Campaigns just as they would normally implement a production campaign – only in a development environment rather than on a live webpage.