Kibana basePAth on ECK

I'm trying to deploy ECK on a local kubernetes cluster with below given spec.

I'm trying to serve kibana ingress using /beats, hence I changed/updated those parameters in config section.
the fleet server never comes online and I can't find out the way out.

apiVersion: kibana.k8s.elastic.co/v1
kind: Kibana
metadata:
  name: kibana
spec:
  version: 8.12.1
  count: 1
  podTemplate:
    spec:
      containers:
      - name: kibana
        livenessProbe:
          tcpSocket:
            port: 5601
          initialDelaySeconds: 5
          periodSeconds: 20
          timeoutSeconds: 10
          successThreshold: 1
          failureThreshold: 30
        readinessProbe:
          tcpSocket:
            port: 5601
          initialDelaySeconds: 5
          periodSeconds: 20
          timeoutSeconds: 10
          successThreshold: 1
          failureThreshold: 30
        env:
          - name: NODE_OPTIONS
            value: "--max-old-space-size=2048"
        resources:
          requests:
            memory: 2Gi
            cpu: 0.5
          limits:
            memory: 2Gi
            cpu: 1
  elasticsearchRef:
    name: elasticsearch
  config:
    server.basePath: /beats
    server.rewriteBasePath: true
    xpack.fleet.agents.elasticsearch.hosts: ["https://elasticsearch-es-http.default.svc:9200"]
    xpack.fleet.agents.fleet_server.hosts: ["https://fleet-server-agent-http.default.svc:8220"]
    xpack.fleet.packages:
    - name: system
      version: latest
    - name: elastic_agent
      version: latest
    - name: fleet_server
      version: latest
    - name: kubernetes
      version: latest
    xpack.fleet.agentPolicies:
    - name: Fleet Server on ECK policy
      id: eck-fleet-server
      namespace: default
      monitoring_enabled:
      - logs
      - metrics
      unenroll_timeout: 900
      package_policies:
      - name: fleet_server-1
        id: fleet_server-1
        package:
          name: fleet_server
    - name: Elastic Agent on ECK policy
      id: eck-agent
      namespace: default
      monitoring_enabled:
      - logs
      - metrics
      unenroll_timeout: 900
      package_policies:
      - package:
          name: system
        name: system-1
      - package:
          name: kubernetes
        name: kubernetes-1
---
apiVersion: elasticsearch.k8s.elastic.co/v1
kind: Elasticsearch
metadata:
  name: elasticsearch
spec:
  version: 8.12.1
  nodeSets:
  - name: default
    count: 3
    config:
      node.store.allow_mmap: true
    podTemplate:
      spec:
        containers:
        - name: elasticsearch
          env:
          - name: ES_JAVA_OPTS
            value: -Xms2g -Xmx2g
          resources:
            requests:
              memory: 2Gi
              cpu: 1
            limits:
              cpu: 1
              memory: 4Gi
    volumeClaimTemplates:
    - metadata:
        name: elasticsearch-data # Do not change this name unless you set up a volume mount for the data path.
      spec:
        accessModes:
        - ReadWriteOnce
        resources:
          requests:
            storage: 20Gi
#        storageClassName: standard
---
apiVersion: agent.k8s.elastic.co/v1alpha1
kind: Agent
metadata:
  name: fleet-server
spec:
  version: 8.12.1
  kibanaRef:
    name: kibana
  elasticsearchRefs:
  - name: elasticsearch
  mode: fleet
  fleetServerEnabled: true
  policyID: eck-fleet-server
  deployment:
    replicas: 1
    podTemplate:
      spec:
        serviceAccountName: fleet-server
        automountServiceAccountToken: true
        securityContext:
          runAsUser: 0
---
apiVersion: agent.k8s.elastic.co/v1alpha1
kind: Agent
metadata:
  name: elastic-agent
spec:
  version: 8.12.1
  kibanaRef:
    name: kibana
  fleetServerRef:
    name: fleet-server
  mode: fleet
  policyID: eck-agent
  daemonSet:
    podTemplate:
      spec:
        serviceAccountName: elastic-agent
        hostNetwork: true
        dnsPolicy: ClusterFirstWithHostNet
        automountServiceAccountToken: true
        securityContext:
          runAsUser: 0
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
  name: fleet-server
rules:
- apiGroups: [""]
  resources:
  - pods
  - namespaces
  - nodes
  verbs:
  - get
  - watch
  - list
- apiGroups: ["apps"]
  resources:
    - replicasets
  verbs:
    - get
    - watch
    - list
- apiGroups: ["batch"]
  resources:
    - jobs
  verbs:
    - get
    - watch
    - list
- apiGroups: ["coordination.k8s.io"]
  resources:
  - leases
  verbs:
  - get
  - create
  - update
---
apiVersion: v1
kind: ServiceAccount
metadata:
  name: fleet-server
  namespace: default
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
  name: fleet-server
subjects:
- kind: ServiceAccount
  name: fleet-server
  namespace: default
roleRef:
  kind: ClusterRole
  name: fleet-server
  apiGroup: rbac.authorization.k8s.io
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
  name: elastic-agent
rules:
- apiGroups: [""]
  resources:
  - pods
  - nodes
  - namespaces
  - events
  - services
  - configmaps
  verbs:
  - get
  - watch
  - list
- apiGroups: ["coordination.k8s.io"]
  resources:
  - leases
  verbs:
  - get
  - create
  - update
- nonResourceURLs:
  - "/metrics"
  verbs:
  - get
- apiGroups: ["extensions"]
  resources:
    - replicasets
  verbs:
  - "get"
  - "list"
  - "watch"
- apiGroups:
  - "apps"
  resources:
  - statefulsets
  - deployments
  - replicasets
  verbs:
  - "get"
  - "list"
  - "watch"
- apiGroups:
  - ""
  resources:
  - nodes/stats
  verbs:
  - get
- apiGroups:
  - "batch"
  resources:
  - jobs
  verbs:
  - "get"
  - "list"
  - "watch"
---
apiVersion: v1
kind: ServiceAccount
metadata:
  name: elastic-agent
  namespace: default
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
  name: elastic-agent
subjects:
- kind: ServiceAccount
  name: elastic-agent
  namespace: default
roleRef:
  kind: ClusterRole
  name: elastic-agent
  apiGroup: rbac.authorization.k8s.io

Now everything comes online except fleet server which is complaining about Kibana endpoint not accessible

k describe agent fleet-server

Events:
  Type     Reason                   Age                 From                                 Message
  ----     ------                   ----                ----                                 -------
  Normal   AssociationStatusChange  22m                 agent-es-association-controller      Association status changed from [] to [default/elasticsearch: Pending]
  Normal   AssociationStatusChange  22m                 agent-kibana-association-controller  Association status changed from [] to [Pending]
  Warning  AssociationError         22m (x7 over 22m)   agent-controller                     Association backend for elasticsearch is not configured
  Warning  AssociationError         22m (x12 over 22m)  agent-controller                     Association backend for kibana is not configured
  Normal   AssociationStatusChange  22m                 agent-es-association-controller      Association status changed from [default/elasticsearch: Pending] to [default/elasticsearch: Established]
  Normal   AssociationStatusChange  22m                 agent-kibana-association-controller  Association status changed from [Pending] to [Established]
  Warning  Delayed                  22m (x5 over 22m)   agent-controller                     Delaying deployment of Elastic Agent in Fleet Mode as Kibana is not available yet
  Warning  ReconciliationError      22m                 agent-controller                     Reconciliation error: secrets "fleet-server-agent-http-certs-public" already exists
  Warning  ReconciliationError      47s (x6 over 21m)   agent-controller                     Reconciliation error: failed to request https://kibana-kb-http.default.svc:5601/api/fleet/setup, status is 404)