I wrote you an xml-code, with this you don't have to manually adjust the time for removing the flag at sunset.
It happens automatically.
I created it for the flag in KMYR with the following times.
DEC-FEB = 08:00-16:00
MAR-MAY;SEP-NOV = 08:00-17:00
JUN-AUG = 08:00-18:00
You can also customize and extend the code.
It should serve you as a template.
XML:
<SODE>
<!-- Data Probe serving its clients -->
<SimObject Name="EDP KMYR">
<Placement Lat="33.67975" Lon="-78.928333" Alt="28" Hdg="0.0"/>
<Model SimTitle="12bPilot_SODE_Environmental_Data_Probe">
<EnvironmentalDataProbe ClientList="US_FLAG_001;US_FLAG_002;US_FLAG_003"/>
</Model>
</SimObject>
<!-- Windspeed range dependent display of different model animations -->
<!-- Wind Direction driven rotation -->
<SimObject Name="US_FLAG_001">
<Placement Lat="33.682103" Lon="-78.922611" Alt="0#AGL" Hdg="0.0"/>
<Model SimTitle="AM_US_Flag">
<ConditionalVisibility LogicExpression="A$B$C">
<Condition ID="A" Variable="WindSpeed" Value="0-99"/>
<Condition ID="B" Variable="MonthOfYear" Value="DEC;JAN;FEB"/>
<Condition ID="C" Variable="Time" Value="0800-1600LT"/>
</ConditionalVisibility>
<VariableDrivenRotation Variable="WindDirection" Axis="HEADING" Animated="No"/>
</Model>
</SimObject>
<SimObject Name="US_FLAG_002">
<Placement Lat="33.682103" Lon="-78.922611" Alt="0#AGL" Hdg="0.0"/>
<Model SimTitle="AM_US_Flag">
<ConditionalVisibility LogicExpression="A$B$C">
<Condition ID="A" Variable="WindSpeed" Value="0-99"/>
<Condition ID="B" Variable="MonthOfYear" Value="MAR;APR;MAY;SEP;OCT;NOV"/>
<Condition ID="C" Variable="Time" Value="0800-1700LT"/>
</ConditionalVisibility>
<VariableDrivenRotation Variable="WindDirection" Axis="HEADING" Animated="No"/>
</Model>
</SimObject>
<SimObject Name="US_FLAG_003">
<Placement Lat="33.682103" Lon="-78.922611" Alt="0#AGL" Hdg="0.0"/>
<Model SimTitle="AM_US_Flag">
<ConditionalVisibility LogicExpression="A$B$C">
<Condition ID="A" Variable="WindSpeed" Value="0-99"/>
<Condition ID="B" Variable="MonthOfYear" Value="JUN;JUL;AUG"/>
<Condition ID="C" Variable="Time" Value="0800-1800LT"/>
</ConditionalVisibility>
<VariableDrivenRotation Variable="WindDirection" Axis="HEADING" Animated="No"/>
</Model>
</SimObject>
<!-- Objects placing -->
<SimObject Name="US_FLAG_Pole">
<Placement Lat="33.682103" Lon="-78.922611" Alt="0#AGL" Hdg="0.0"/>
<Model SimTitle="AM_Flag_Pole">
<ConditionalVisibility Variable="Time" Value="1600-0800LT"/>
</Model>
</SimObject>
</SODE>