What is the latest time a pilgrim can be present at Arafah during Hajj for it to be valid, and what must the pilgrim do in this case?

The last time a pilgrim can attain the standing (wuquf) at 'Arafah is before the dawn of the tenth of Dhul-Hijjah. If dawn breaks and the standing has not occurred, the pilgrim has missed the Hajj. Whoever stood at 'Arafah before dawn has attained the standing, but according to the Malikis, a sacrifice (dam) is due if they did not stand for a portion of the day. It is obligatory to combine both night and day in the standing. So, whoever departs before sunset owes a sacrifice (dam) if they do not return, but if they arrive there at night and stand there, no sacrifice is due.