he asked Aishah about the Witr of the Prophet. She said: "He would perform Witr during all of the night; (either) its beginning, its middle, or its end. So when he died, his Witr ended, during the approachof As-Sahar."  

عَنْ وِتْرِ رَسُولِ اللَّهِ ﷺ فَقَالَتْ مِنْ كُلِّ اللَّيْلِ قَدْ أَوْتَرَ أَوَّلِهِ وَأَوْسَطِهِ وَآخِرِهِ فَانْتَهَى وِتْرُهُ حِينَ مَاتَ إِلَى السَّحَرِ