It's been more than a few weeks now since Microsoft first allowed Windows Insiders to "Skip Ahead" to preview the next Windows 10 19H1 update. However, if you've been holding off on opting into this special ring of the Windows Insider program, you're now out of luck as enrollment is now closed.
We're not certain on the specific date when enrollment first closed, but we tried to enroll one of our Insider Machines to the Skip Ahead branch today and received the "closed" message seen in the featured image above (looks like MSPU noticed it, too). It is kind of surprising to see that it took this long for enrollment to close up, as enrollment previously shuttered up in under a week with the last Windows 10 development cycle.
At any rate, only those who did manage to opt to Skip Ahead will now continue to see new Windows 10 features and updates for stock apps like Sticky Notes, Mail, and Photos. Insiders on the other rings (who also opted into the Windows App Preview Program) will also still see updates for specific inbox apps, but will only likely get Redstone 5 bug fixing and quality builds moving forward.
The overall news should not be shocking, as Microsoft mentioned on multiple occasions that it will be closing off Skip Ahead once the maximum number of seats are filled. The company also specifically limited enrollment to Skip Ahead and "Forked" the Insider program in order to ensure quality feedback on 19H1 builds, but not shift attention away from Redstone 5 development.