Permission to pray Duha from the time the sun is high until noon

Riyad as-Salihin (The Meadows of the Righteous)

by Imam Nawawi

207. Chapter: Permission to pray Duha from the time the sun is high until noon. It is best to pray it when it is very hot and well into mid-morning

1143. Zayd ibn Arqam said that he saw some people praying at the beginning of the time of Duha. He said, "Do they not know that the prayer at a later time is better? The Messenger of Allah, may Allah bless him and grant him peace, said, 'The prayer of the repenters is when the young camels have become hot from the sun.'" [Muslim]