ESA

I am currently off sick and receiving ssp. I have had brain surgery and a stroke but have been working in the same office for 30 years. I do not thimk i will be fit to return to work so dont want to claim ssp and then go on to esa and rettire then. Just wonderimg if i retired on ill health now would i be able to claim the esa contrinution rate or do i actually have to wait until the 28 weeks ssp ends. It just seems disloyal as my vompany are paying the ssp and i probably wont be returning. Thank you