Extrinsic 18937-1

{
  "heartbeat": {
    "blockNumber": 18935,
    "sessionIndex": 315,
    "validatorsLen": 4,
    "authorityIndex": 2
  },
  "signature": "0x548744d5848f45937077d7b9c52146e82a9c30df71ed2680d5850b58778c9a20c28e97a2699ae71ac746163bc32929ca7c92b6dd3a806e00680395ffe5dadb8f"
}