Questione giuridica chiave
Whether the federal appeal was filed within the statutory deadline.
Decisione estratta
The appeal supplement filed on 19 September 2013 was late; only the filing of 8 September 2013 was timely.
Motivazione estratta
The 30-day deadline under Art. 100 Abs. 1 BGG began on 20 August 2013 and expired on 18 September 2013; the extension filed after that date could not be considered.