I don't want to give you wrong ingformation (because I am not in the same situation) but I thought I can still reply to your question. Even when you are fully funded, you need to register/enrol to your course every year anyway, so I assume the university would be interested to find out whether or not you can pay the current year's fee only. On the other hand, I suggest not to give up and apply for other funding. Contact the University to ask for departmental funding, contact other grant-giving bodies. Good luck with the AHRC funding by the way...