Hi David,
Thanks for reaching out.
Hopefully I can help clear up the confusion you described.
Each release starts in the "Targeted" phase, where we offer the new update to specific, targeted devices, as we mange the roll out. With 1803, we adopted the use of AI, and saw both much faster velocity and better user experience as a result. This is the basis of our servicing guidance that we provide to commercial customers as well. With a new release, provide it to a subset up users in an early servicing ring, and with good data and feedback met, add more users through additional targeting rings until you meet your deploy decision criteria, at which point you the update everyone else. This mirrors what we just completed with the Windows Update managed devices.
If an issue is found during any point of a release lifecycle, preview, targeted or broad, with windows, we work to quickly understand the issue, generate a fix in Windows if the bug is ours, or work with the 3rd party if the issue is not ours. For issues that are ours, we create and ship both quality fixes as well as security fixes each month, you don't have to wait for a new feature release ( 1809 ), just the next monthly patch Tuesday perhaps. It is the agile servicing that has enabled us to quickly address and unblock devices during a roll out, and why we have been able to achieve the velocity we just saw with 1803 with the highest quality and best user experience yet for Windows 10.
As an ISV, your Windows Compatible apps will work from release to release, which is the experience 100,000Ks of apps and 100s Millions devices demonstrate and experience with each feature update. Yes, of course, we see issues as well. This is rare, but we actively monitor, investigate and work to correct when it happens, either with the fix ourselves, or working with the ISV/Driver owner.
Thanks
John