exactly this happened to me... twice

first time it didnt' slip off fully and i hammered it back on and drove home with a loud popping sound from the leaky joint

2nd time, it fell off completely and i had to take off the rest of the zorst and stuff it in a mate's car. was about 10ks from home. drove home loudly and just turned off the motor and coasted down hillls

the design of this type of LCB annoys me so much. why have the joint for the collector in such a place that it can fall off. like GeoffP says: with a maniflow type LCB the joint is horizontal, so even if ur supports break or otherwise, at least the thing won't fall off the car.