Threshold 2 is expected to be rolled out sometime in November, which was reportedly planned for an October release initially, though Microsoft decided to delay the release of the non-patch update until November.
Reasons for delaying the upcoming update can be attributed to a number of reasons. As pushing the update to a later date gives them more time to polish and fine tune the new features and changes included with the update, that should eventually bring a more stable build for Windows 10 users.
http://www.inferse.com/35750/microsoft-delays-windows-10-threshold-2-november/