I was inspecting my back brakes and noticed the backplate was distorted away from the drum , then found it was rusted right through in several places, which came as a bit of a surprise...
It is very common to see distorted backplates as they are often used to lever the drums off. The rust around the perimeter is not too critical, but how good/bad are the rest of the plates?
They can be replaced with Mini back plates, although that will mean having to use the all steel brake adjuster set up.