Extrinsic 18313-1

{
  "heartbeat": {
    "blockNumber": 18312,
    "sessionIndex": 305,
    "validatorsLen": 4,
    "authorityIndex": 1
  },
  "signature": "0x763c699c7327d318839ef10e6a033f078d49987112f84386f710419b053d45766e48e2ee3d5c179dd37b588b4807ede95744eb8e3a8e1b175d8629335285a88f"
}