Server2016 RDS farm 21.007.20091 update error

Since the 14th September we have had the following issues after Adobe Reader tried to update itself from 21.005.20060 to 21.007.20091

Server 2016 RDS farm. We get a bit of a mixture of things happening.
When opening from the start menu:

• Users get a windows installer prompt with a progress bar stating 'Preparing application for first use'
• Then an RdrServicesUpdater.exe - Application Error notification "The application was unable to start correctly (0xc0000142). Click OK to close the application." But Adobe opens fine.

If opening a PDF file from explorer it can open fine for 2 or 3 times in a row. But then get a mixture of the above. Sometimes the installer appears upon close.

Additionally the folder path C:\Program Files (x86)\Adobe\Acrobat Reader DC\Reader

contains multiple folders 'acrocef_1' through to 'acrocef_32' which is using 5.2GB of data on a very small C: drive.

I checked the link Basic Configuration — Deployment Planning and Configuration (adobe.com) 

It showed how to disable updates in the Adobe Customization Wizard. 
I had already used this wizard to check the box to 'Disable Product Updates' & create a transforms file to customize the installer.
When I checked in the registry at (As mentioned in post above)

HKLM\SOFTWARE\Policies\Adobe\(product name)\(version)\FeatureLockdown\
bUpdater DWORD was set to '0'

&
HKLM\SOFTWARE\WOW6432Node\Policies\Adobe\(product name)\(version)\FeatureLockdown\
bUpdater DWORD was set to '0'

But the link says to:
Disable updates to the web service plugins by setting HKLM\SOFTWARE\Policies\Adobe\(product name)\(version)\FeatureLockdown\cServices\bUpdater to 0.
bUpdater within the cServices key did not exist.
I created this on our Development server (& in WOW6432Node) and restarted. Logged in as an admin no issues. Logged in as a user and still getting the same thing.

This seems like a bug with version 21.007.20091.
But if i revert back to 21.005.20060 - without a way to disable updates. How long until this issue come back by itself?

Please let's have a correct method to disable updates and a patch for current version.

We are getting so many support calls from users about this issue.