Microsoft is now testing Windows 10 build 17099 internally. This new Windows 10 Redstone 4 (v1803) build 17099 (10.0.17099.1000 rs4_prerelease.180208-1426) was compiled on Fab 08, 2018. Windows 10 build 17100 might roll out to Insider next week.
The software giant is also preparing to release its first Windows 10 Redstone 5 build 17600 to Skip ahead insiders.
Windows 10 preview build 17093 is now available for the Insiders. The latest insider preview build comes improvements for the Game bar, Diagnostic Data, Graphics improvements, Eye Control, Windows Security, Bluetooth, Microsoft Edge, Input, Windows App Permissions, Ease of Access improvements and much more.
The ISO files for Windows 10 build 17093 are also now available for download. You can download it from the link below.