Microsoft has released Windows 10 for phones build 10052 to Insiders

[anuseems]

Microsoft has released a new Windows 10 for phones build 10052 to Fast ring users; this build is a small update to build 10051, which was released a few days ago

From Neowin:

It's a good day for Windows Phone users as Microsoft has released a new build of Windows 10 for phones, build 10052. The release follows up the previous build, 10051, that was released several days ago but had stability issues.

You can download the build now by checking for an update but know that since this build is one version newer than what was previously released, don't expect much in terms of new features. In fact, Microsoft said that this build is targeted at bug fixes, so hopefully anyone who was having major issues with the previous release will find this build more stable.

http://www.neowin.net/news/microsoft-has-released-windows-10-for-phones-build-10052-to-insiders