Changing course - Durham

Ive defered my entry into durham undergrad until next september. With this time ive been sort of rethinking my course (archaelogy and classical civilisations). I was wodering if anyone knew durhams policy on changing courses. When i applied to durham they dropped my grade requirements which i acheived, but i didnt get the original grades hown on ucas for my course, or courses similar. I wondered if they would refer to these grades, or the dropped grades if they were to require it. Hopefully someone knows, thanks