Start specifying v3.4 for the metrics image version.
MODIFY
ansible/roles/openshift_metrics/defaults/main.yml
ansible/roles/openshift_metrics/defaults/main.yml
@@ -6,3 +6,4 @@ osamet_hawkular_limits_memory: 3G
osamet_hawkular_requests_memory: 2G
osamet_heapster_limits_memory: 3.75G
osamet_heapster_requests_memory: 0.9375G
+osamet_image_version: "v3.4"

MODIFY
ansible/roles/openshift_metrics/tasks/main.yml
ansible/roles/openshift_metrics/tasks/main.yml
CASSANDRA_PV_SIZE: "{{ osamet_pv_size }}"
CASSANDRA_NODES: "{{ osamet_cassandra_node }}"
IMAGE_PREFIX: registry.ops.openshift.com/openshift3/
+ IMAGE_VERSION: "{{ osamet_image_version }}"
reconcile: False
register: processout
- debug: var=processout

Start specifying v3.4 for the metrics image version.