Extrinsic 15262-1

{
  "heartbeat": {
    "blockNumber": 15261,
    "sessionIndex": 254,
    "validatorsLen": 4,
    "authorityIndex": 2
  },
  "signature": "0x26ed6886a88b7c1a81ddd6926959134a7f5b28f34cdf4b760057a78898300220b9635e8f62283d4364c0a0e382903be418ceea2f5bdef0e6ac8314be41ac2389"
}