Dear Mrs Cooper,
I am writing with some news that I am afraid you may find disappointing. I will have to leave the flat earlier than planned.
My company has transferred me to its head office in Manchester, and I have to start work there on 1 September. I had hoped to stay until the end of my contract in January, and I am sorry for any inconvenience this causes you.
I have been very happy here, and I will miss the neighbourhood. According to my notice period, I can move out on Friday 28 August, and I will make sure that the flat is clean and in good condition before I go.
I would like to help you find a new tenant as quickly as possible, so that you do not lose any rent. I could put an advertisement on the university noticeboard and on a few websites, and I could show people around in the evenings.
Thank you very much for your understanding.
Yours sincerely,
Victoria Hughes