Microsoft has compiled its first Windows 10 Redstone 6 (19H1) build 18200 and now testing it internally. Windows 10 v1903 build 18200 (10.0.18200.1000 rs_prerelease.180716-1422) was compiled on July 16, 2018. Like earlier RS5 builds, Windows skip ahead Insiders will get first chance to test new RS6 builds in upcoming weeks.
Currently, Windows 10 Redstone 5 build 17713 is available for Fast Ring Insider members. The latest insider build includes a big list of improvements for Microsoft Edge, Notepad, Windows Defender Application Guard, and more. In addition, build 17713 has added a new “Web Sign-in” option to the Windows PC. Web Sign-in enables Windows logon support for non-ADFS federated providers (e.g. SAML).
In other news, no new Windows 10 insider build will roll out this week. A new Redstone 5 build will be available next week.