to get on to the business course i do agree is a bit hard due to the demand so if u were asked to get ABB and came back with say a BBB it may be ok but anything lower you may not get what course you INITALLY applied for - now thats a point to note bcuz say uve applied for IBML (international business and languages) and you dint make the grade they may ask you to do a combined honour instead (so you'd be doing Business admin. w/ a language) This totally depends on what you want, if you reallllly want to be at aston, explore the possibilites of an alt. degree but keep in mind combined honours are not on the same level as the actual business skl degree (not that Im knocking anythng but this is what Ive been told time after time)
Now aside from cut throat competition for aston seats is in Pharmacy, business, chemical eng,optometry- they seem really flexible with grades and will be willing to offer even with a lower grade.