Microsoft has announced a change to Fast Ring for Insiders. From now on the Fast Ring was receive builds from the active development branch (called “RS_PRERELEASE”), meaning new features will show up in these builds as Microsoft is working on it.
While features in the active development branch may be slated for a future Windows 10 release, they are no longer matched to a specific Windows 10 release. This means that builds from the active development branch simply reflect the latest work in progress code from Microsoft engineers.
New features and OS improvements done in this branch during these development cycles will show up in future Windows 10 releases when they are ready and may be delivered as full OS build updates or servicing releases.
Microsoft notes this will avoid the issue of Fast Ring users not having access to the latest features as has been the case with limited size Skip Ahead rings.