I am not qualified to give you qualified answer on this (lol,) BUT, at Castio Farms Farm Fest, one of the speakers had developed a time released edible that released four doses of THC through the day, basically every 4-6 hours, but he did it using different oils he said. He was saying that certain oils process much faster in the body, and other oils process much, much slower.
So it sounds like the type of oil used itself can make a big difference in how it absorbs in your body (or at what rate.)
But again, this is me regurgitating his explanation.