Adding snapshot action to ISM

We have an OpenSearch cluster running 2.19 which we use to store logs.

We currently delete logs after 10 days.

{
    "policy": {
      "description": "Delete logs after 10 days",
      "default_state": "hot",
      "ism_template": [
        { "index_patterns": ["main-*"], "priority": 100 }
      ],
      "states": [
        {
          "name": "hot",
          "actions": [],
          "transitions": [
            { "state_name": "delete", "conditions": { "min_index_age": "10d" } }
          ]
        },
        {
          "name": "delete",
          "actions": [
            { "retry": { "count": 3, "backoff": "exponential", "delay": "1m" }, "delete": {} }
          ],
          "transitions": []
        }
      ]
    }
  }

This is working as expected. We now want to add a step to back them up to S3 before deleting. We have added the S3 bucket to Repositories in OpenSearch and did a Snapshot to ensure all permissions are working. I can see the .dat files in the S3 bucket.

However, trying to update the policy is causing an issue

{
    "policy": {
      "description": "Send to S3 then delete after 10 days":,
      "default_state": "hot",
      "ism_template": [
        { "index_patterns": ["main-*"], "priority": 100 }
      ],
      "states": [
        {
          "name": "hot",
          "actions": [],
          "transitions": [
            { "state_name": "archive", "conditions": { "min_index_age": "10d" } }
          ]
        },
        {
          "name": "archive",
          "actions": [
            {
"retry": {
"count": 5,
"backoff": "exponential",
"delay": "30m"
},
              "snapshot": {
                "repository": "main-app-logs-bucket",
                "snapshot": "{{ctx.index}}-{{ctx.execution_time}}"
              }
            }
          ],
          "transitions": [
            { "state_name": "delete" }
          ]
        },
        {
          "name": "delete",
          "actions": [
            { "retry": { "count": 3, "backoff": "exponential", "delay": "1m" }, "delete": {} }
          ],
          "transitions": []
        }
      ]
    }
  }

This get's an error saying

You have actions that are not allowed in your policy [snapshot]