Development releases are not production ready
Development releases are snapshots of the ongoing Confluence development process. While we try to keep these releases stable, they have not undergone the same degree of testing as a full release, and could contain features that are incomplete or may change or be removed before the next full release.

No upgrade path
Because development releases represent work in progress, we cannot provide a supported upgrade path between development releases, or from any development release to a final release. You may not be able to migrate any data you store in a Confluence development release to a future Confluence release.

No support
Atlassian does not provide support for development releases.