Had more oddness today when mine went off and never came back up. Curiously it tallied with another SNMP log, but I can't see why that would cause issues with booting afterwards.
Rebooted it ten hours later and it came back up... with a
yellow LED (which no documentation references)
Be interesting to see if VM tells me the reason, but I imagine it'll just be another replacement Hub, as always seems to be the case!
Tom