I rented a room in my apartment to a new lodger under the Rent-a-room scheme. They moved in a week and a half ago and paid me one RENT payment in advance for the month, as is the usual practice (I am not talking about the deposit, that's another story). The other day I told them to move out as I was not happy with their behaviour and other things. I have given them 4 weeks to move out. If they find a new place before the next rent payment, do I owe them rent back?