When authoritativeAPI is ClusterAPI, update mapi machineset template, such as update instanceType from m6i.xlarge to m5.xlarge, the mapi machineset instanceType value is changed to m5.xlarge. 

4.19.0-0.nightly-2025-05-08-151714

Always

1. Create a new mapi machineset with authoritativeAPI: ClusterAPI
2. Update mapi machineset instanceType from m6i.xlarge to m5.xlarge 
3. Check capi awsmachinetemplate and mapi machineset instanceType value
     

mapi machineset instanceType is changed to m5.xlarge, awsmachinetemplate instanceType is m6i.xlarge

 $ oc get machineset.m zhsunaws-lwwcm-worker1 -o yaml   
apiVersion: machine.openshift.io/v1beta1
kind: MachineSet
metadata:
  annotations:
    capacity.cluster-autoscaler.kubernetes.io/labels: kubernetes.io/arch=amd64
    machine.openshift.io/GPU: "0"
    machine.openshift.io/memoryMb: "16384"
    machine.openshift.io/vCPU: "4"
  creationTimestamp: "2025-05-09T09:42:05Z"
  generation: 10
  labels:
    machine.openshift.io/cluster-api-cluster: zhsunaws-lwwcm
  name: zhsunaws-lwwcm-worker1
  namespace: openshift-machine-api
  resourceVersion: "271577"
  uid: 34f4c5dd-b5bf-40c0-a00a-f5689a6e8f4d
spec:
  authoritativeAPI: ClusterAPI
  deletePolicy: Oldest
  replicas: 1
  selector:
    matchLabels:
      machine.openshift.io/cluster-api-cluster: zhsunaws-lwwcm
      machine.openshift.io/cluster-api-machineset: zhsunaws-lwwcm-worker1
  template:
    metadata:
      labels:
        machine.openshift.io/cluster-api-cluster: zhsunaws-lwwcm
        machine.openshift.io/cluster-api-machine-role: worker
        machine.openshift.io/cluster-api-machine-type: worker
        machine.openshift.io/cluster-api-machineset: zhsunaws-lwwcm-worker1
    spec:
      authoritativeAPI: ClusterAPI
      lifecycleHooks: {}
      metadata:
        labels:
          machine.openshift.io/cluster-api-cluster: zhsunaws-lwwcm
          machine.openshift.io/cluster-api-machineset: zhsunaws-lwwcm-worker1
          node-role.kubernetes.io/worker: ""
      providerSpec:
        value:
          ami:
            id: ami-0f13d2cbfbca6203b
          apiVersion: machine.openshift.io/v1beta1
          blockDevices:
          - ebs:
              deleteOnTermination: true
              encrypted: true
              kmsKey:
                id: ""
              volumeSize: 120
              volumeType: gp3
          capacityReservationId: ""
          credentialsSecret:
            name: aws-cloud-credentials
          deviceIndex: 0
          iamInstanceProfile:
            id: zhsunaws-lwwcm-worker-profile
          instanceType: m5.xlarge

$ oc get awsmachinetemplate -n openshift-cluster-api zhsunaws-lwwcm-worker1 -o yaml       
apiVersion: infrastructure.cluster.x-k8s.io/v1beta2
kind: AWSMachineTemplate
metadata:
  annotations:
    cluster.x-k8s.io/paused: ""
  creationTimestamp: "2025-05-09T09:42:05Z"
  generation: 1
  name: zhsunaws-lwwcm-worker1
  namespace: openshift-cluster-api
  ownerReferences:
  - apiVersion: cluster.x-k8s.io/v1beta1
    blockOwnerDeletion: true
    controller: false
    kind: Cluster
    name: zhsunaws-lwwcm
    uid: 44ae0887-a95b-43c1-9248-db9d643a84dd
  resourceVersion: "211587"
  uid: 2488eb27-673a-40e6-ae28-64069de14b5f
spec:
  template:
    metadata: {}
    spec:
      additionalSecurityGroups:
      - filters:
        - name: tag:Name
          values:
          - zhsunaws-lwwcm-node
      - filters:
        - name: tag:Name
          values:
          - zhsunaws-lwwcm-lb
      additionalTags:
        kubernetes.io/cluster/zhsunaws-lwwcm: owned
      ami:
        id: ami-0f13d2cbfbca6203b
      cloudInit: {}
      iamInstanceProfile: zhsunaws-lwwcm-worker-profile
      ignition:
        storageType: UnencryptedUserData
        version: "3.4"
      instanceMetadataOptions:
        httpEndpoint: enabled
        httpPutResponseHopLimit: 1
        httpTokens: optional
        instanceMetadataTags: disabled
      instanceType: m6i.xlarge

When authority is capi, update mapi machineset template, the value should be restored to the original value.