It's been two weeks since the last Windows 10 SDK Insider Preview was released, but there's a new Slow ring build, which means a new SDK.
In the announcement, Microsoft also said that it's releasing Mobile Emulator build 15240, which it also said last time, and the time before that when it was actually released on August 22. It's just another example of how the company seems to forget that Windows 10 Mobile is even a thing in the Insider Program, along with Slow ring builds that never get announced and Fast ring builds on days where it was promised that there would be none.
The news comes alongside the release of ISOs for Windows 10 for PCs build 16278, which is a bit peculiar, given that normally the Slow ring, SDK, and ISOs are all on the same page. Brandon LeBlanc confirmed on Twitter that Microsoft has some issues posting ISOs, and all should be back to normal soon.