Each time Cumulus has restarted the wind direction data history graph afterwards has displayed an obvious anomaly in that the data from before the restart show "wind direction" equal to "average", while after the restart appears proper.
here is an example as the wind direction data appeared on my Cumulus-generated website today some hours after a Windows Update inspired computer restart.

Is this a Cumulus bug? Or is it likely I've got something wrong in my installation that is causing this?
Somehow I don't feel it likely that this is properly described as a feature.