The 9.x.x package stream has been an experimental stream that was used to get early access to a number of forthcoming features in SRP and Hyrbid renderer. Now that Unity 20.2 is in beta this stream will stop being maintained. All changes from this package stream have been rolled into the 10.x.x release stream. 10.x.x will be the verified package in 20.2 and included as part of the Unity installer. The 10.x.x stream is available via package manager if you are on Unity 20.2.