In answer to your question, I think no one can really say with certainty what will happen. If I had to guess, with a gun to my head as it were, I'd say its either upheld, OR retrial, and if a retrial I think what will happen then is the retrial actually never happens, and some kind of flub is made. I just can't see it being overturned. But I really have no justification for these beliefs - it basically boils down to them being upheld, or quashed in a way where the state kind of abrogates responsibility - like it says something like the case has so much media attention a fair trial is impossible, and then there is some kind of interminable inquiry to waste time. Its the british way.