This build is a new Technical Preview release. The main addition in this build is a new Windows Phone-style notification area. Otherwise, it is quite similar to 9841. The buildtag was initially found through the ThresholdInternal build update mechanism on 2014-10-10. The build was released to those signed up to the Windows Insider Program on 2014-10-22 and can be downloaded via the Preview Builds build update mechanism in build 9841.