Blow coming from cat

Hi guys, this is my first post on this and was really just looking for any advice. Just today my 2001 330i touring has managed to begin blowing at the join section of the downpipe and the cat. It's just next to the sensor and I'm unsure as to how long it will take until proper damage is done. I've had it up on ramps and my fears are that the exhaust from the cat back will need to be replaced. Any help or advice is greatly appreciated. Cheers boys!