Like a hole in a dam, the erosive force of the oil combined with sand and silt will act like a sandblower gradually widening the escape channel/pipe and resulting in an increasing escape flow over time. It seems at this point the escaping oil will continue until the resevoir beneath it is depleted to the point that the pressure in the underground oil deposit is equalized with the outside pressure at the sea floor, after that it will simply be a leak capable of being sealed.
Live video link from the ROV monitoring the damaged riser
Live video link from the ROV monitoring the damaged riser
