SQL Server 2016 to 2019 now SSRS Cannot create a connection to data source

[how2trainyourdragon]

We upgraded from SQL Server 2016 to 2019, and our reports on the report server now say:

An error has occurred during report processing. (rsProcessingAborted)
Cannot create a connection to data source 'DataSource1'. (rsErrorOpeningConnection)
A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: Named Pipes Provider, error: 40 - Could not open a connection to SQL Server)
The network path was not found

If I download the report and/or run the original from my box via Visual Studio, the report works.

 

[how2trainyourdragon]

We got the report to work by changing our datasource connection string InStr() to uppercase for the first parameter, and the new server URL is uppercased.

Our expression works now after updated to the following, but problem is we have 50+ report to now do this for. Looks like this was due to a fix:
KB4535706 makes SSRS Report URL's Case Sensitive

="Data Source=server-" &
IIF(IsNothing(Globals!ReportServerUrl), "app",
Switch(
InStr(Globals!ReportServerUrl, "-BBSQL-"),"app",
InStr(Globals!ReportServerUrl, "-CCSQL-"),"app2"
))
& "-" &
IIF(IsNothing(Globals!ReportServerUrl),"devl",
Switch(
InStr(Globals!ReportServerUrl, "-DEVL"),"devl",
InStr(Globals!ReportServerUrl, "-BETA"),"beta",
InStr(Globals!ReportServerUrl, "-PROD"),"prod"
)
) & ";Initial Catalog=" & Parameters!DB.Value