@Retired_mod -
We are customer of databricks. Have databricks premium workspace with unity catalog enabled. and we have also legacy workspaces (non-unity enabled).
I can see history is available for all workspaces (unity and non-unity) in same meta store region.
Regarding retention - storage location is as below, looks like data is store in control plane on databricks. Since data is not stored in data plane, we can't configure LCM on our end. Currently it is preview will this change in once it becomes GA?
Storage location: uc-deltasharing://system.access.audit#system.access.audit