Key legal question
Whether the cantonal court rightly refused to hear the appeal as late despite a wrong appeal instruction.
Extracted holding
The late filing was not excused by trust protection because the wrong instruction could have been recognized with due diligence, especially by counsel.
Extracted reasoning
The 20-day appeal period under the special planning statute was clear from the order itself and from the cantonal provisions; an attorney must at least perform a basic check of the applicable legal remedy period.