Extrinsic 1248-1

{
  "heartbeat": {
    "blockNumber": 1245,
    "sessionIndex": 20,
    "validatorsLen": 4,
    "authorityIndex": 3
  },
  "signature": "0x400d02da3c4637e20b084281c47f05362064add66316c81dd345fc8bf8db9d431279e473dda02041d220d2c1dc45e04626f37352455711fcd2b6c63ee9a79888"
}