The Life Cycle for ARO [1] is not the same than the Life Cycle for OCP, and at the time of writing, 4.6, 4.7 and 4.8 releases are EOL. But the information in the "Details" of the cluster shows those versions as "Maintenance support" (as they are in "Maintenance support" for OCP):

Also, the link to the "Life cycle" page links the OCP page:

When the "Type" of the cluster is ARO, the "Life cycle state" should show the correct information and link to the correct page.

[1] https://docs.microsoft.com/en-us/azure/openshift/support-lifecycle#azure-red-hat-openshift-release-calendar