Some tips i discovered while setting this thing up:
Some games (not all) when the system detects it has a Series S/X Enhancements it will prompt you to download the update which generally is the entire game. If the game resides on an External HDD or USB 3.0, the system will delete that copy at one point when it is downloading the newer/updated version it is installing to the internal drive. Dirt 5 for some reason it did not do this...but so far all my other games get removed from their old locations.
I also learned that if you move a game that is Series S/X enhanced to the internal drive "BEFORE" it is updated, it will just erase it and download the new version. I think many thought it would just download what it needs to make it the enhanced but it seems it is the entire game that needs to be redownloaded. So moving your games over is almost pointless unless they are games that are not enhanced and you just want them to load a bit quicker.
For me it didn't remove the the games from the external automatically I had to do it manually for every game.