Cannondaleriders

I have read other post on a breather hose update. I would like to see this is the problem I am having. At my last race I notice oil dripping from the airbox, I took the air filter off and it was soak in motor oir. I started the engine and it seemed as oil was coming out of the brass fitting in the airbox. I am assuming this is the breather hose. I traced it back to the top back right portion of the frame. Is this true? And is it for ventilation? And why did it all of a sudden after months of riding did it start blowing oil? Please help.