I don't know if this is a bug or this is how the program works and it is a limitation.
The "Related Zone" field is actually generated for the Wall, not the Surface of the Wall.
So, if I understand it correctly, when you schedule the "Related Zone" field for a Surface, it will list the Related Zone of the Wall the Surface is part of. This is why both Zones are listed for both Surfaces.
I am not completely sure about this so I will forward this to GRAPHISOFT. Let us see what they say about it.
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