ESA Assessment form received after a few years

Hi Dear, Thank you firstly for being for us. I received ESA assessment form after hearing nothing for a couple of years, is it mandatory for them to send new form? Last time, I followed your detailed guide and it was successful. Can you tell me if I should read your updated version (Mar 18)? Is there any different than previous ones? I need to ask as it is a huge volume. Also, shall I include what I wrote in my last form? My mental condition has deteriorated due to aging and also having lost lot of weight, etc. I appreciate your kind help again! Many thanks