Microsoft has said there will be no new releases for the Windows Insider Program this week. The company says it will resume updating with preview releases next week. The reasons for the (admittedly) slight delay is to allow Microsoft to upgrade the backend of the Insider Program.
More specifically, the company will upgrade the systems that approve Insider builds and make sure they run smoothly. These services are used to decide is a build is ready to be rolled out to Windows Insiders. Once approved, these builds are moved from the Development Branch to the Insider rings.
In an announcement, Windows Insider Program chief Dona Sarkar tweeted about the delay. Microsoft says the Windows Insider Program settings may not function properly until after the upgrade. This means you will not be able to sign up for the program in that time, or change rings.
— Dona Sarkar at #AbilitySummit (@donasarkar) September 7, 2016
Microsoft's statement says:
“We are performing some upgrades this week to our services that are used to approve and monitor builds from the Development Branch to our Windows Insiders. Once the upgrade is complete, just as we flight the OS through the rings, we will be flighting the service upgrades through the internal rings first. We won't have any new builds from the Development Branch for you this week, but plan to return to schedule next week.”
It is perhaps telling of the success of the program that even a week delay is worthy of an announcement. The Windows Insider Program has been pushing out preview builds on a near constant basis to users. Indeed, Microsoft is rolling out one preview or another mostly every week.
This was particularly important in the development of the Windows 10 Anniversary Update. The company tested all Redstone 1 features with Insiders, allowing them to give feedback. Armed with the feedback, the company could make necessary changes to the service. A tactic like this meant end users were not aware of many bugs and niggles in early release features.