It doesn't happen they are locked in there. I won't use them again unless I'm sure I won't have to take them out, good bit of kit if you don't want to take them out. Maybe a screwdriver and hammer. Anyway they are out now and polyfilla in. Swans down and second coat on ceiling tomorrow.
They lock on to the back of the plasterboard, so if they don't unlock then I'd imagine you can't push it through, well unless you want a bigger hole in you wall lol.


