Land planning for a triangular plot

Plot? There is a land use plan that was newly implemented two years ago. The entire area is designated as residential land. However, no legal claim to development can be derived from the mere existence of the land use plan.

Yes, you are right.
But the office's reasoning is then incorrect. Because according to the current land use plan, the plot is not in an outer area. Perhaps a sensitive negotiation with the building authority might have been successful here. I would be interested in the architect's reasoning as to why nothing stands in the way of dividing the plot.

Yes, you are right there. Perhaps a sensitive negotiation with the building authority would have been successful here.

You are preaching to the choir with me, our lawyer had already tried. There was apparently also a preliminary vote (the wording of which I do not know), which would have resulted in the approval of the decision. Unfortunately, this seems to have been somehow forgotten during the course of the procedure.