´Ja'far bin Muhammad bin 'Ali bin Al-Husain narrated from his father, that Jabir bin 'Abdullah said:` "The Messenger of Allah (ﷺ) prayed Subh as soon as he was certain the dawn had appeared."
Hadith Referenceسنن نسائي / كتاب المواقيت / 544
Hadith Gradingالألبانی:صحيح | زبیر علی زئی:صحيح مسلم
´Humaid narrated from Ans that a man came to the Prophet (ﷺ) and asked him about the time of the Subh prayer. The following morning he commanded that the Iqamah for prayer be said when dawn broke, and he led us in prayer. The next day when there was light he commanded that the Iqamah for prayer be said and he led us in prayer. Then he said:` "Where is the one who was asking about the time for prayer? (It is) between these two times."
Hadith Referenceسنن نسائي / كتاب المواقيت / 545
Hadith Gradingالألبانی:صحيح الإسناد | زبیر علی زئی:حسن