Consequence for departing Arafah before sunset and returning during the day to stand until sunset.
Chapter on the Description of Hajj
Al-Mughni
Book of Hajj
Primary text
If one departs before sunset but returns during the day and stands until sunset, no sacrifice (Dam) is required. This is the view of Malik and Al-Shafi'i. The justification is that the person fulfilled the required obligation of standing during both night and day, thus removing the need for a penalty, similar to one who crosses the Miqat boundary without being in Ihram but then returns to assume Ihram from that point.
Supporting text
The Kufans and Abu Thawr hold that a sacrifice is due because the obligation for the Dam was incurred by the initial departure before sunset, and that obligation is not lifted by returning, just as if one returned after sunset.