When a parcel of land under one ownership at the time of the adoption of the resolution is divided by a zone district boundary line and the dividing of such a parcel is consistent with the purpose and intent of this resolution and each portion may support a reasonable and legal use, then the zone district boundary line shall be as determined by the scale of the zone district map. Any dispute regarding a zone district line shall be heard by the County Planning Commission. In the event the Commission finds the zone district line is not consistent with the purpose and intent of said resolution, the Commission shall prepare an appropriate recommendation to the Board of County Commissioners.