Windows 10 Enterprise: How to receive branch upgrades through Windows Update

I just noticed that branch upgrades (e.g. TH2) are in fact available through WU, but by default are only offered when activated via MAK.
However, there is a check for the following registry value that enables KMS-activated installations to receive the upgrades as well:

Code:

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\WindowsUpdate\OSUpgrade]
"AllowKMSUpgrade"=dword:00000001

(Obviously, this does not apply to LTSB.)