Microsoft had released Windows 10 Redstone 4 Preview Build 17133 that was believed by many to be the Release to Manufacturers (RTM) build. Sometimes, officials will confirm a build is RTM, as in "Release to Muggles". The move is unprecedented, as it's the first time that a feature update as arrived in the Release Preview ring - which is designed for updates that will eventually arrive for non-Insiders - and has been replaced by a newer build due to a bug.
The public release of the next Windows 10 version was expected earlier in this month. The earlier detected bugs should be fixed with this new build, and it's likely this will be the actual final version of Redstone 4 that rolls out to everyone.
It is not news that the release of the Spring Creators Update for Windows 10 has been delayed, and in a blog post today Microsoft's Dona Sarkar detailed the issue.
Ironically, a recent update to Instagram for Windows 10 to version 30.1569.12133.0 added some excellent features but removed the option to install the app on handsets running the mobile version of OS. The company said that the build carries no new features and only brings fixes for some issues. In certain cases, these reliability issues could have led to a higher percentage of (BSOD) on PCs for example.
There is speculation that the final public release of Version 1803 might be a few weeks away yet. And will need to test a cumulative update with it, too. However, a blocking bug was discovered that delayed the release to the public nearly at the last minute. Or, hop in our Windows 10 Forums for more discussions and troubleshooting advice for all things Microsoft.