Microsoft is now testing Windows 10 version 1803 build 17021 for PCs internally. The new Redstone 4 Update build 17021 (10.0.17021.1000 rs_prerelease.171016-1458) was compiled on Oct 16, 2017.
Windows 10 version 1709 (Fall Creators Update) is now available for everyone. You can now download official Windows 10 Fall Creators Update ISO from here. A new cumulative update KB4043961 (OS build 16299.19) is also available for end users. The update comes with bug fixes and minor improvements.
Windows 10 Redstone 4 update build 17017 is available for Fast and Skip ahead insiders. It brings new Cortana features including Cortana Collections and more. Also, there are bug fixes and improvement to the OS.
