This is the way to prevent the automatically upgrade of Office 365 ProPlus 2013 to 2016
Solution 1: Change the Registry
Go to the following location in the registry on each affected computer:
HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\office\15.0\common\officeupdate
Add the following value under the office update subkey:
“enableautomaticupgrade“=dword:00000000
Solution 2: GPO
Add
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