Microsoft has released Windows 10 build 14393.479 to Insiders enrolled in the Release Preview ring in the form of updates. If you are not enrolled in this ring, don't worry as the updated cumulative update will reach your PC very soon.
There is currently no change log that lists the changes the update brings, so once again it is not known what you will put on your computer. 
The update's support page only states:
This update includes improvements and fixes to enhance the functionality of Windows 10 Version 1607.
or in English:
This update includes improvements and fixes to enhance the functionality of Windows 10 Version 1607.
Hopefully, the company will provide more information after the necessary testing by Insiders and the release of the information to the general public.
The update has the ID KB3201845.
Since it's still a cumulative update, it should release all the performance improvements and security fixes to the Windows 10 stable channel after a short period of time.
If you are enrolled in the Release Preview Ring, open Settings and go to Update and you will see the new cumulative update.
If you have installed previous updates, only the new fixes that are contained in this package will be downloaded and installed on your computer. If you are installing a Windows 10 update package for the first time, the package for the x86 version is 503 MB and the package for the x64 version is 937 MB.
Alternatively, you can use the links below.
