This is a cold startup test - both the sensor and the gateway were powered on at the same time from a fully powered off state.

There were some other sensors in the area that were picked up by the LoRa device. The test sensor (and only one registered in Chirpstack) has a devEUI ending in 1f5.

If I've understood the association between device and joinRequest correctly, then the first time the device joined it had a devAddr ending in 887, and the second time it ended in 088.