Applied at 2 unis, can I accept a studentship and turn it down later?

I've applied to do a PhD at two universities and received an offer from both. I've just won a studentship from my second choice of university (Warwick), and I have two weeks to confirm if I want to accept it. I really want to go to my first choice (Manchester), but they won't be awarding studentships for about another two months according to my prospective supervisor, and I don't want to risk not getting funding. Would I be able to accept this studentship and then turn it down later if I get a studentship at my first choice, or will that disqualify me? Another consideration is rent - I already live in Manchester with my family, and if I can do my PhD here I won't have to worry about rent and I'll be able to save.

So I was in this scenario before, very much so, I had recieved a studentship from the uni of lancaster and it was great woo... but not the PhD project i reallly really wanted.... had two weeks to accept so i went to the last second with lancaster and accepted because uea (phd i wanted) was taking its time to respond. and after i got offered my second one, i sent the email to cancel... depending on the formalities of the university, some may require you to attend inductions and stuff like that, as well as organising rent etc. but again the lack of position is really the worst... id say just to commit the PhD you got offered, accept it, and then later down the line you can turn it down... gotta think about yourself, but be sure to keep the supervisor in a good place, the world is small and you might cross paths with them esp if its in similar areas.