Change of circumstances

Hi, I receive pip. I reported a change of circumstances because i believe Im no longer meeting a descriptor due to some improvement. They told me I will receive a form through the post and will probably have another assessment after that. There doesn’t seem to be a lot of clear guidance on how to fill that form in. Dwp said you only need to fill in what has changed. Some other advice says fill every part in but be brief with an example for answers where there’s no change. I’ve also seen where you should fill it out in detail. Im so overwhelmed with it right now. I don’t see the point in filling every detail in as they already have that info. My gut is telling me to just fill in what has changed and for the rest of the questions just give a brief example of why those descriptors haven’t changed. Any advice?