The Prophet ﷺ said, "Eat and drink until Bilal calls the adhan."
أن النبي ﷺ قال: كلوا واشربوا حتى يؤذن بلال.
No references are available.
Abu Yaala (4385) narrated it from Musab bin Abdullah, who said, Ibn Darawardi narrated to me, from Hisham bin Urwa, from Urwa, from Ayesha, and he related it.Darawardi is Abdul-Aziz bin Muhammad, and the phrase "Ibn Darawardi" contains an extra "Ibn" which is perhaps a copyist's error. Ibn Khuzayma (406) also narrated it by this same route, and from him Ibn Hibban (3472), and its chain of transmission is sahih, and its essential content is found in the Sahihayn. See the Book of Adhan.