https://www.theregister.co.uk/2018/07/26/windows_insiders_see_double_as_new_windows_10_builds_arrive/

Microsoft gave Windows Insiders a double treat last night and threw a bone to the dedicated crowd of Windows Mixed Reality users.

The announcement sees build 17723 lobbed onto the branch targeting release this Autumn and build 18204 giving a first taster of the delights to come to Windows 10 next spring.