I’ve just discovered that if you update a Windows 10 installation using a memory stick that has the latest version on it will update it to the next version and not the latest version.
Let's talk versions
Windows 10 version
Windows 10 Release (1505)
November Update (1511)
Anniversary Update (1607)
Creators Update (1703)
Fall Creators Update (1709)
April 2018 Update (1803)
October 2018 Update (1809)
Mat 2019 Update (1903)
Released
29/07/2015
10/11/2015
02/08/2016
05/04/2017
11/07/2017
18/01/2018
28/03/2019
21/05/2019
Expiry date
End of service
End of service
End of service
End of service
End of service
End of service
12/11/2019
08/12/2020
You would expect that you can install the latest version of Windows 10 onto a computer with a memory stick that has the May 2019 Update on it onto a Windows 10 April Update, but what it will do is install the October Update instead. Only once you have installed this Update, you can install the May Update.
However, considering it takes several hours to update to that version, updating from an old version is a right pain.
In the past, they had Service Packs which had to be installed in order, and it appears this is what you have to do now, even though you have the latest version, it will only install the next Service Pack (now called an Update)