Hi @David Zemdegs ,
> What is a GDR please?
Quote from this MS document;
GDR (General Distribution Release): A GDR is typically associated with a critical patch release the product groups feels should be provided to and installed by the whole customer base. GDRs are often associated with security releases, or other critical fixes needed to mitigate a problem the majority of customers will experience when using our product.
Please check your SQL server setup log to find the SQL server upgrade information. The setup log files are located at %programfiles%\Microsoft SQL Server\nnn\Setup Bootstrap\Log by default.
Refer to MS document View and Read SQL Server Setup Log Files.
> Might it be a Windows server 2019 update or an update to .NET framework?
No, these operations will not cause SQL server update.
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