I asked ʿAisha, "How is the prayer of Messenger of Allah ﷺ during the month of Ramadan." She said, "Messenger of Allah ﷺ never exceeded eleven rakʿat in Ramadan or in other months; he used to offer four rakʿat-- do not ask me about their beauty and length, then four rakʿat, do not ask me about their beauty and length, and then three rakʿat." Aisha further said, "I said, 'O Messenger of Allah ﷺ! Do you sleep before offering the witr prayer?' He replied, 'O ʿAisha! My eyes sleep but my heart remains awake'!"  

أَنَّهُ أَخْبَرَهُ أَنَّهُ سَأَلَ عَائِشَةَ ؓ كَيْفَ كَانَتْ صَلاَةُ رَسُولِ اللَّهِ ﷺ فِي رَمَضَانَ فَقَالَتْ مَا كَانَ رَسُولُ اللَّهِ ﷺ يَزِيدُ فِي رَمَضَانَ وَلاَ فِي غَيْرِهِ عَلَى إِحْدَى عَشْرَةَ رَكْعَةً يُصَلِّي أَرْبَعًا فَلاَ تَسَلْ عَنْ حُسْنِهِنَّ وَطُولِهِنَّ ثُمَّ يُصَلِّي أَرْبَعًا فَلاَ تَسَلْ عَنْ حُسْنِهِنَّ وَطُولِهِنَّ ثُمَّ يُصَلِّي ثَلاَثًا قَالَتْ عَائِشَةُ فَقُلْتُ يَا رَسُولَ اللَّهِ أَتَنَامُ قَبْلَ أَنْ تُوتِرَ فَقَالَ يَا عَائِشَةُ إِنَّ عَيْنَىَّ تَنَامَانِ وَلاَ يَنَامُ قَلْبِي  

I did not see the Prophet ﷺ reciting (the Qur'an) in the night prayer while sitting except when he became old; when he used to recite while sitting, and when thirty or forty verses remained from the Sura, he would get up and recite them and then bow.  

مَا رَأَيْتُ النَّبِيَّ ﷺ يَقْرَأُ فِي شَىْءٍ مِنْ صَلاَةِ اللَّيْلِ جَالِسًا حَتَّى إِذَا كَبِرَ قَرَأَ جَالِسًا فَإِذَا بَقِيَ عَلَيْهِ مِنَ السُّورَةِ ثَلاَثُونَ أَوْ أَرْبَعُونَ آيَةً قَامَ فَقَرَأَهُنَّ ثُمَّ رَكَعَ