"Bilal calls the Adhan during the night, so eat and drink until Ibn Umm Maktum calls (the Adhan)" (Using translation from Nasāʾī 637)   

«إِنَّ بِلَالًا يُؤَذِّنُ بِلَيْلٍ فَكُلُوا وَاشْرَبُوا حَتَّى يُؤَذِّنَ ابْنُ أُمِّ مَكْتُومٍ»  

[Machine] The Prophet ﷺ had two muadhins, Bilal and Ibn Umm Maktum. The Messenger of Allah ﷺ said, "If Bilal gives the adhan at night, then continue eating and drinking until you hear the adhan of Ibn Umm Maktum." Al-Qasim said, "There was nothing between them except this one would descend while the other ascends."  

كَانَ لِلنَّبِيِّ ﷺ مُؤَذِّنَانِ بِلَالٌ وَابْنُ أُمِّ مَكْتُومٍ فَقَالَ رَسُولُ اللَّهِ ﷺ «إِنَّ بِلَالًا يُؤَذِّنُ بِلَيْلٍ فَكُلُوا وَاشْرَبُوا حَتَّى تَسْمَعُوا أَذَانَ ابْنِ أُمِّ مَكْتُومٍ» فَقَالَ الْقَاسِمُ وَمَا كَانَ بَيْنَهُمَا إِلَّا أَنْ يَنْزِلَ هَذَا وَيَرْقَى هَذَا