question #3 Sahih al-Bukhari 1099, Book 18, Hadith 19 : What is the difference between Nawafil and compulsory prayers in terms of direction and posture?

The Prophet (ﷺ) used to pray (the Nawafil) on his Mount facing east and whenever he wanted to offer the
compulsory prayer, he used to dismount and face the Qibla.