As said, KB4530684 (2019-12 cumulative update is three times offered and three times successfully installed.
In contrast, 2020-01 cumulative update is not yet offered.
Any action to be taken, or just wait?
Windows 64 bit Pro v1909
After a fourth successful installation I decided to delete the content of the Software Distribution folder, as mentioned in several internet publications.
After that, nothing happened after checking for updates: You are up to date.
Then I learned that there are reasons not to activate "checking for updates", see for instance:
Don’t Click “Check for Updates” Unless You Want Unstable Windows 10 Updates
or
Here is another reason to avoid "check for updates" in Windows 10 - gHacks Tech News
I just waited for some weeks, and yes: updates appear now automatically.
After two days same updates were again "successfully installed".
Issue not solved.
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