Cloud Gaming recently available to Core subscribers?

 I am an Xbox insider with a game pass core subscription.

How do I access cloud gaming on the web or tv xbox app as an xbox insider? Each time I try to launch a game on the web or tv app, I am prompted to upgrade to ultimate game pass subscription. 

I understand that I should have access to cloud gaming because of : ​https://news.xbox.com/en-us/2025/08/27/xbox-insiders-can-stream-and-play-in-new-ways-with-xbox-game-pass-starting-today/

Do I need to make any changes in order to access cloud gaming of games I own on the web/tv Xbox app with a game pass core subscription? Thank you for your support.