Friday 8 December UTC 12:28 and the Sensor Hub upgrade still hasn't been published. All still at 4.10 (only in the beta archives has there been a 5.30 version):
Fenix 5X
http://www8.garmin.com/support/download_details.jsp?id=11427
Fenix 5s
http://www8.garmin.com/support/download_details.jsp?id=11433
Fenix 5
http://www8.garmin.com/support/download_details.jsp?id=11437
Forerunner 935
http://www8.garmin.com/support/download_details.jsp?id=11497
This surely must trigger strange results on the watches...