If he is in his employer's scheme he needs to ask at work. Employers/Schemes don't grant these things easily though as it's expensive for them and they need to be sure your husband will be unable to carry out any kind of work.
Is he completely unable to work for at least 2 years?
Has he exhausted his company sick pay?
... sorry if my reply seemed unsympathetic- I was just trying to seek information and set out my understanding. It doesn't sound a nice condition- I wish you both well.
My friend had to leave work at 63. He gets pension credit and they pay his stamp until his retirement age. He also has a small works pension. Phone pension credits they are very helpful and nice people to deal with.