According to the WordPress core team, only the latest active version of WordPress is actively supported.
The WordPress core team attempts to backport security updates to older versions when possible, but there are no guarantees, and no timeframe for updating older releases. This can mean that sites running older versions of WordPress cannot benefit from important security measures that may be publicly known. Point (minor) releases, in particular, are often security releases, or contain important security updates and bug fixes.
The VIP team manages upgrades for major, minor, and security releases for all VIP Platform environments running WordPress.
Advance notice and details of upcoming major release versions are posted in the VIP Lobby. As a major release approaches, non-production environments should be upgraded to the new release version so that applications can be validated prior to the upgrade on production.
Development teams are expected to test WordPress releases through the beta and release candidate periods. This can be managed by switching over local development environments to use the Beta Tester plugin or updating the locally running version of WordPress to trunk via either SVN or GitHub.
- “Trunk” contains the latest development code in preparation for the next major release cycle of WordPress. It is the newest possible version, but not necessarily a stable version. It includes Alpha and Beta versions and changes often.
Environments running “Trunk” versions will continue to track trunk until explicitly changed.
- “Branch” contains directories that consist of the latest code for each major release, and minor release development occurs within the branch.
Environments running “branch” versions will be upgraded to the release version on release day.