Kernrechtsfrage
Whether A transferred his tax residence to Y or Z and thus ended Swiss tax liability from 1 August 2013.
Extrahierter Entscheid
No. A did not establish a new tax residence abroad; he retained his Swiss residence in X because he returned to Switzerland after missions and kept his apartment available.
Extrahierte Begründung
For tax residence abroad, the decisive factor is the intention of permanent stay, proved by objective circumstances. A's temporary housing and contacts abroad were insufficient; he did not acquire a lasting center of life there and kept returning to his apartment in X.