9 Dhu al-Hijjah at 10 a.m.: If the person comes only then and leaves before zawal, the stated time has not begun.
9 Dhu al-Hijjah in the afternoon: Presence at Arafat occurs within the window.
10 Dhu al-Hijjah at 3 a.m., before dawn: The time is still open.
10 Dhu al-Hijjah after dawn: The window has closed.
These illustrations address timing only, not the other conditions for valid Hajj.