Extrinsic 308-1

{
  "heartbeat": {
    "blockNumber": 307,
    "sessionIndex": 5,
    "validatorsLen": 4,
    "authorityIndex": 0
  },
  "signature": "0x980e0a966c900074412d8ad059515eb8c183baacc447f140a35cc7310a3d417eb7ca2f9fe09c3a80e4181d95c62895ee7fd46611d73054b28748ff72e528f387"
}