There was a validation issue that has since been fixed.
Verified in 4.8.0-0.nightly-2021-04-29-222100, REMOVEDINRELEASE shows empty instead of "2.0": $ oc get apirequestcount NAME REMOVEDINRELEASE ... REQUESTSINLAST24H alertmanagerconfigs.v1alpha1.monitoring.coreos.com ... 1851 alertmanagers.v1.monitoring.coreos.com ... 105 ... clusterrolebindings.v1.rbac.authorization.k8s.io ... 9221 clusterrolebindings.v1beta1.rbac.authorization.k8s.io 1.22 ... 18 ...
Since the problem described in this bug report should be resolved in a recent advisory, it has been closed with a resolution of ERRATA. For information on the advisory (Moderate: OpenShift Container Platform 4.8.2 bug fix and security update), and where to find the updated files, follow the link below. If the solution does not work for you, open a new bug report. https://access.redhat.com/errata/RHSA-2021:2438