I submit for document traveling and employment from british immigration.
I Am Malaysian And In The Uk Without A Visa, How Long Am I Allowed To Stay?
No one is allowed to stay in UK without Visa. I am not sure how you are living there. If you are self-employed then still you need business visa there. You have to leave as soon as possible before some legal action will be taken against you.
I think it's three or six months, but you might want to check with the british embassy to get the correct answer