What penalties will incur if I break my lease agreement early?
You should not enter into a legally binding contract unless you can fulfil its terms including the length of the tenancy. In general, you can only end the tenancy early if your landlord agrees. Your landlord does not necessarily have to do so.
You will remain responsible for paying the rent until the end of the tenancy contract or the next break clause point. However, if your landlord agree to re-market the property before this, then once a new tenant is found your liability to the rental payment will be reduced pro rata. You will be asked to cover any of the landlord's financial loss as a result ending the tenancy early. This may include the landlord letting fees (which he cannot recover) and any other landlord expenses associated with the re-letting. If you are unsure, talk to a KFH letting agent or your landlord before making any plans.