The source recognizes:
Watan al-Asli — a permanent home, such as the place of birth or a place adopted as a lasting home. It is invalidated only by establishing another Watan al-Asli.
Watan al-Iqamah — a place where one validly intends to stay 15 days or more. It is ended by another Watan al-Iqamah, a new qualifying journey, or returning to Watan al-Asli.
The source then says the critical jurists do not treat a short-stay 'Watan al-Sukna' of less than 15 days as a separate full legal Watan category. The earlier course version incorrectly presented it as a full third Watan type.