Bug 2036717

tested with the PR, still see the error, prometheus-operator version is 0.53.1, but prometheus-operator resource version label is still 0.53.0
# oc -n openshift-monitoring logs prometheus-operator-58dfffc4c6-8qhpg | head
level=info ts=2022-01-04T02:06:21.031156379Z caller=main.go:217 msg="Starting Prometheus Operator" version="(version=0.53.1, branch=master, revision=f09f225f4)"
...

# cat <<EOF | oc apply -f -
apiVersion: monitoring.coreos.com/v1alpha1
kind: AlertmanagerConfig
metadata:
  name: example
spec:
  route:
    groupBy: ['job']
    groupWait: 30s
    groupInterval: 5m
    repeatInterval: 12h
    receiver: 'null'
    muteTimeIntervals:
    - feb
  muteTimeIntervals:
  - name: feb
    timeIntervals:
    - months:
      - february
  receivers:
  - name: 'null'
EOF
The AlertmanagerConfig "example" is invalid: spec.muteTimeIntervals.timeIntervals.months: Invalid value: "february": spec.muteTimeIntervals.timeIntervals.months in body should match '^((?i)january|febuary|march|april|may|june|july|august|september|october|november|december|[1-12])(?:((:((?i)january|febuary|march|april|may|june|july|august|september|october|november|december|[1-12]))$)|$)'

# oc -n openshift-monitoring get deploy prometheus-operator -oyaml
apiVersion: apps/v1
kind: Deployment
metadata:
  annotations:
    deployment.kubernetes.io/revision: "1"
  creationTimestamp: "2022-01-04T02:06:15Z"
  generation: 1
  labels:
    app.kubernetes.io/component: controller
    app.kubernetes.io/managed-by: cluster-monitoring-operator
    app.kubernetes.io/name: prometheus-operator
    app.kubernetes.io/part-of: openshift-monitoring
    app.kubernetes.io/version: 0.53.0
  name: prometheus-operator
  namespace: openshift-monitoring
  resourceVersion: "7338"
  uid: da1d4562-118f-47ff-b647-b63b25a86f9e
spec:
  progressDeadlineSeconds: 600
  replicas: 1
  revisionHistoryLimit: 10
  selector:
    matchLabels:
      app.kubernetes.io/component: controller
      app.kubernetes.io/name: prometheus-operator
      app.kubernetes.io/part-of: openshift-monitoring
  strategy:
    rollingUpdate:
      maxSurge: 25%
      maxUnavailable: 25%
    type: RollingUpdate
  template:
    metadata:
      annotations:
        kubectl.kubernetes.io/default-container: prometheus-operator
        target.workload.openshift.io/management: '{"effect": "PreferredDuringScheduling"}'
      creationTimestamp: null
      labels:
        app.kubernetes.io/component: controller
        app.kubernetes.io/managed-by: cluster-monitoring-operator
        app.kubernetes.io/name: prometheus-operator
        app.kubernetes.io/part-of: openshift-monitoring
        app.kubernetes.io/version: 0.53.0

# oc get crd alertmanagerconfigs.monitoring.coreos.com -oyaml
...
                          months:
                            description: Months is a list of MonthRange
                            items:
                              description: MonthRange is an inclusive range of months
                                of the year beginning in January Months can be specified
                                by name (e.g 'January') by numerical month (e.g '1')
                                or as an inclusive range (e.g 'January:March', '1:3',
                                '1:March')
                              pattern: ^((?i)january|febuary|march|april|may|june|july|august|september|october|november|december|[1-12])(?:((:((?i)january|febuary|march|april|may|june|july|august|september|october|november|december|[1-12]))$)|$)
                              type: string
                            type: array

tested with above PRs, followed steps in Comment 0, no error now
# oc -n openshift-monitoring logs prometheus-operator-65f7676954-j8tsc | head
level=info ts=2022-01-04T10:55:29.204254018Z caller=main.go:217 msg="Starting Prometheus Operator" version="(version=0.53.1, branch=master, revision=f176cb1ac)"

# oc get crd alertmanagerconfigs.monitoring.coreos.com -oyaml
...
                          months:
                            description: Months is a list of MonthRange
                            items:
                              description: MonthRange is an inclusive range of months
                                of the year beginning in January Months can be specified
                                by name (e.g 'January') by numerical month (e.g '1')
                                or as an inclusive range (e.g 'January:March', '1:3',
                                '1:March')
                              pattern: ^((?i)january|february|march|april|may|june|july|august|september|october|november|december|[1-12])(?:((:((?i)january|february|march|april|may|june|july|august|september|october|november|december|[1-12]))$)|$)
                              type: string
                            type: array

prometheus-operator-65f7676954-j8tsc           2/2     Running   0             29m   app.kubernetes.io/component=controller,app.kubernetes.io/managed-by=cluster-monitoring-operator,app.kubernetes.io/name=prometheus-operator,app.kubernetes.io/part-of=openshift-monitoring,app.kubernetes.io/version=0.53.1,pod-template-hash=65f7676954

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 4.10.3 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-2022:0056