Kernrechtsfrage
Whether the administrative appeal was still admissible after the appellants withdrew it before the department.
Extrahierter Entscheid
No. The withdrawal was clear, unconditional, and effective; the original building authority decision became final, so a fresh challenge before the Administrative Court was barred.
Extrahierte Begründung
A valid withdrawal waives substantive review and renders the appealed decision final. The court found no vitiating factors, no reliance interest, and no indication of an overhasty or defective waiver.