When does the first hour of Friday begin and end for the purpose of attaining the virtue of early attendance at Friday prayer?

The scholars differed on determining the start of the first hour on Friday with three opinions: the first is from dawn, the second is from sunrise, and the third is an hour after zawal (declination of the sun). The correct view is that the hours begin from sunrise, and the time between sunrise and the Dhuhr adhan (definition) is divided into five parts, such that each part is the "hour" intended in the Hadith (definition). This is supported by what Ibn Qudamah and Al-Nawawi mentioned, that the arrival of the Imam folds the scrolls, so there is no virtue for whoever comes after zawal.