As long as you get the required points.
From then your CV, interview skills, internal testing, degree classification and experience comes to play.
Basically your a levels and degree kind of filters you when applying, as many employers ask for 2:1 or above, so even if your Oxford grad with a 2:2, chances are tight. From then they may be considered less important.
Work experience > a resit which MAY bump an A to A*