Tested with 4.3.0-0.nightly-2020-03-25-232436, KubeVersionMismatch alert is removed
# token=`oc -n openshift-monitoring sa get-token prometheus-k8s`
# oc -n openshift-monitoring exec -c prometheus prometheus-k8s-1 -- curl -k -H "Authorization: Bearer $token" 'https://prometheus-k8s.openshift-monitoring.svc:9091/api/v1/rules' | jq | grep "KubeVersionMismatch"
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, and where to find the updated
files, follow the link below.
If the solution does not work for you, open a new bug report.