Fiqh-us-Sunnah Volume 5, Hajj and ‘Umrah, Fiqh 5.107A.

The time appointed for throwing pebbles during the three days is from midday until sunset. Ibn ‘Abbas reported that the Prophet (peace be upon him) threw the pebbles at midday or thereafter. This is reported by Ahmad, Ibn Majah and Tirmizhi who consider it a sound hadith.

Al-Baihaqi has reported on the authority of Nafi’ that Abdullah bin ‘Umar used to say “We used not to throw the pebbles during the three days until after the sun was past the meridkul. Delaying the throwing of pebbles till night was disliked. The time for throwing pebbles dul-ing the night was until the sunrise of the next day. All Imams of Islamic law. except Abu Hanifah, agree on this point. Abu Hanifah holds that throwing pebbles before midday on the third day is permissible. He based his opinion on a rather weak hadith transmitted by Ibn ‘Abbas which says, “When day breaks on the 13th of Zhul-Hijjah, it is permissible to throw one’s pebbles and depart from Mina (to Makkah).”