Extrinsic 18702-1

{
  "heartbeat": {
    "blockNumber": 18701,
    "sessionIndex": 311,
    "validatorsLen": 4,
    "authorityIndex": 0
  },
  "signature": "0x6aa45b8a2c640ebb2d4b57275e2ef34047060d93e3abed3672ef28c72ed76b1b06c169bf632b342b2919c9b722d903f3d03578e280242acf9e8f50a943eb3885"
}