In my last update I said I would report back on Wednesday, April 15, 2020 concerning the incremental/differential issue after a Windows 10 Cumulative update. I lied. But in my defence, how was I expected to know that the move to a new host would be undertaken that week!
I am happy to report that not a single differential has occurred since April 6th. Cumulative updates were processed on April 14th and 15th. There have also been 12 updates to other applications without any issues. Which included updates to iTunes and iCloud which had been problematic.
The 4 files that the Storagecraft Tech replaced on April 6th seemed to have done the trick.
Hopefully the next feature release of Windows 10 (2004) will not mess up the environment.