Yet another build leak suggest that Microsoft is now testing Windows 10 build 16259 for PCs internally. The new Redstone 4 update build 16259.1000 (rs_prerelease.170801-1645) was compiled on August 1, 2017.
In addition, the company also compiled mobile build 10.0.15238.0 (feature2.170731-1756) on July 31.
Recently, Windows Insider team released the Fall Creators Update build 16257.0 and Windows 10 Redstone 4 build 16257.1000 to Fast Ring insiders. The builds were released with new features, bug fixes, and improvements.
Microsoft is also expected to release Windows 10 Cumulative update build 14393.1593 (Anniversary Update) and update build 10586.1045 (Threshold 2) on August 8.
Now you can download Windows 10 build 16257 ISO from the link below.