The time for duha begins when the sun is about a spear’s length above the horizon and it continues until the sun reaches its meridian. It is preferred to delay it until the sun has risen high and the day has become hot.
Zaid ibn Arqam relates: “The Messenger of Allah sallallahu alehi wasallam went to the people of Quba’, and they were performing duha, and he said: ‘The prayer of devotion should be observed when the young weaned camels feel the heat of the sun.'” This is related by Ahmad, Muslim, and at-Tirmizhi.
Fiqh-us-Sunnah Volume 002, Supererogatory Prayer, Fiqh 2.031A.
…May Allah give us a better understanding & guide us to accept the truth