I am York Summer Term Student ( May 1)
I had to defer my admission from Winter to Summer since, they took more than 1 month to accept.
After sending all documents on October, They scanned and sent back to my brother living there. I was like worried it was more than month and no reply. Then my brother called them again, and they were like they forgot to check my IELTS document ! My brother sent docs again and finally the acceptance letter came on December, mid. It was to late to apply for Visa! So I had to defer to Summer term.
If you are applying at York, you need to keep them and yourself updated all the time.