Appealing pip

hi everyone im new to the site so im hoping ive posted in the correct forum .my husband was on dla for 15 years not easy 15 years had to appeal twice won both cases .had a car had that taken away by only getting low mobility.changed from dla to pip had low mobility removed .got low care for 3 years .had f2f  scored no points at all so i requested mr no change .now going through appeal stages been 28 weeks wait still no date .i have since done a letter to the appeal explaining my husbands issues and how it affects me being with him for 43 years .i did no know that appeal board send all letters to dwp as well .i have since had a long appointment with is mental health dr who as wrote a letter explaining the issues the illness medication and that he as fears that someone is going to poison is food ect .he keep checking doors windows and he feels that someone out there is setting him up . he as psychotic medication that makes him very tired and irritable  also as he never passes security when asked by the dwp for me to speak on his behalf .ive now been ,made is appointee ....how long did your appeal take from start to finish .....thank you