It's not all over unless he has proved that he ate contaminated meat, rather than just presenting a hypothesis. He certainly hasn't mentioned it to date. If he has no proof this will go to the IOC, and the UCI will have to decide if it is comfortable having no credibility whatsoever.
Looking at the Cycling News story, this is exactly what's happening - by overturning the ban for no good reason, UCI lose any credibility they had left.
1) Contador tests positive for Clenbuterol, says it was accidental from contaminated meat, receives ban.
2) Contador appeals, his legal case is: "but I ate contaminated meat!"
3) Apology accepted, all will be forgotten by the first week in July.