This was pushed to my Windows 10 image YESTERDAY from Microsoft Update but the content is still not visible to describe the changes/fixes, etc. I'm on Release Preview which historically updates and KB were on the below public link.
https://support.microsoft.com/en-us/help/12387/windows-10-update-history
Log Name: System
Source: Microsoft-Windows-WindowsUpdateClient
Date: 8/16/2016 4:34:18 PM
Event ID: 44
Task Category: Windows Update Agent
Level: Information
Keywords: Started,Download
User: SYSTEM
Computer: xxxxxx
Description:
Windows Update started downloading an update.
<EventData>
<Data Name="updateTitle">Cumulative Update for Windows 10 Version 1607 for x64-based Systems (KB3176932)</Data>
<Data Name="updateGuid">{B77DC257-753A-4C59-B56C-A5FA03C3582A}</Data>
<Data Name="updateRevisionNumber">203</Data>
</EventData>