They are using slow ring and fast ring for updates
A new approach to updates and upgrades
the most revolutionary change in Windows 10 is the concept of continuous improvement.
New features are delivered through Windows Update rather than being set aside for the next major
release. In a major change of longstanding best practices, Microsoft now recommends that enterprise
customers enable Windows Update for the majority of users, although the option to use Windows Server
Update Services (WSUS) might still be available for some configurations.
In the Windows 10 Technical Preview, the more-or-less monthly new builds are delivered through Windows Update. Participants in the preview program can choose between two update speeds, also known as
rings. Choosing the Fast ring makes new builds available as soon as they’re released by Microsoft; opting for the Slow ring delays the availability of a new build until it’s been thoroughly vetted
by the Fast ring, with any bugs addressed via interim updates.
When Microsoft officially releases Windows 10 to the public, the preview program won’t end. Members of the Windows Insider program will continue to receive early access to new updates, using the same Fast and Slow rings. Windows users who are not part of the preview program will receive updates for what’s known as the “Current Branch.” In addition, Microsoft has committed to an additional approach for enterprise customers who want a more stable environment, with a “Current Branch for Business” that is several months behind the consumer releases as well as “Long Term Servicing” branches that are appropriate for mission-critical applications.
read this
Introducing Windows 10 for IT Professionals, Preview Edition
http://www.microsoftvirtualacademy.com/ebooks#9780735696969