Extrinsic 15277-1

{
  "heartbeat": {
    "blockNumber": 15276,
    "sessionIndex": 254,
    "validatorsLen": 1,
    "authorityIndex": 0
  },
  "signature": "0x2688e7360fc8c016e60afe8fe8396f04802ee77f8583511057980588ce76a7580e31f68f3ae1189a08c4c1f5ab394439eae0e87f0b8c4ba02a232046e4335986"
}