In 2009 Hadj runs from November 25 - 29.
Just read a little about it. Each person walks counter-clockwise seven times about the Ka'bah, the cube-shaped building which acts as the Muslim direction of prayer; kisses the Black Stone in the corner of the Kaaba; runs back and forth between the hills of Al-Safa and Al-Marwah; drinks from the Zamzam Well; goes to the plains of Mount Arafat to stand in vigil; and throws stones in a ritual Stoning of the Devil. The pilgrims then shave their heads, perform a ritual of animal sacrifice, and celebrate the three day global festival of Eid al-Adha.
Walking, kissing, drinking, running, standing, throwing stones, shaving your head and sacrificing animals. Yeah, I can see why you wouldn't want to interrupt any of that to announce an oil deal.
But what's wrong with the 11 days between now and then?