HD Powerview Error Messages Every Night at 00:49 AM

I am using the Hunter Douglas (Luxaflex) Powerview Binding and I notice that every night at 00:49 it reports the same series of errors as follows…

2019-09-18 00:49:15.143 [ERROR] [rview.internal.HDPowerViewWebTargets] - Bridge returned 423 while invoking : {"userData":  <redacted> }

2019-09-18 00:49:15.152 [WARN ] [ternal.handler.HDPowerViewHubHandler] - No response to shade poll

2019-09-18 00:50:22.430 [WARN ] [ternal.handler.HDPowerViewHubHandler] - Unexpected error connecting to bridge
javax.ws.rs.ProcessingException: java.net.ConnectException: Connection refused (Connection refused)
.. long java debug trace omitted

Does anyone know why this happens? And what do I need to do to make it go away?