I recently upgraded a version 10.8.1 enterprise SQL Server geodatabase to version 11 using ArcGIS Pro 3.0 Upgrade Geodatabase GP tool. Doing so, come to find out by design, altered the way the geodatabase items are named. In v11 it no longer uses the [databasename].[schema].[tablename] format and is now only [schema].[tablename]. This change broke all of my enterprise paths in models and python scripts for things like feature class paths, field mapping paths, etc. I wasn't expecting that, and it was a big chore to repair. Please update the documentation to warn of that change when upgrading between geodatabase versions prior to v11.
https://pro.arcgis.com/en/pro-app/latest/help/data/geodatabases/manage-sql-server/upgrade-geodatabas...