These are the ones which expand outwards and towards the rear side of the
plasterboard as the screws are tightened for the first time.
I now need to remove them and the only thing that I can think of is to put a
screw in a little of the way and then try to hammer them back to their
original 'long' shape before trying to pull them out. However, I could end
up spoiling the wall even more in the process and I'm sure that someone here
knows a better way to do this. Any advice please ?