I have sometimes wondered this, I suppose if it is clearly defined in the contract under what circumstances they would be removed and that has been met i.e. health test results, specific level of placings at shows, etc. then I think an appeal to the KC might be succesful. How you say to a breeder "I think you look a bit doddery would you mind doing this" is another matter :) But then it would be reasonable to ask for things to be spelled out to avoid missunderstandings later anyway.
I write into my puppy contract that if I die the endosements may be lifted by my executers subject to certain conditions being met. My executers would be my sons, I of whom is very doggy, the others would well understand as well.