Today, Microsoft released Windows 10 SDK Preview build 16267. There"s been no announcement for it yet, so the "release notes" link just takes you to the blog post for build 16257.
And to be clear, 16257 is also the latest Windows 10 build in the Fast ring, which is something that you may want to be aware of if you choose to install the new SDK Preview. If you attempt to target build 16267, you won"t be able to test your app.
It"s been 20 days now since we"ve seen a new Windows 10 build, but Microsoft"s Dona Sarkar says that there may be one tomorrow. Until then, you might want to stick with SDK build 16257, as we know that it"s been platform-complete for some time.
Mobile Emulator Insider Preview build 15240 is also available, and luckily, that actually corresponds to a build that was released in real life. You can download the latest Windows 10 SDK and Mobile Emulator Previews here.