Conviction as in they were sentenced to 25 (Raffaele) and 26 (Amanda) years pending the appeal process they are currently going through, for the sake of discussion if they lost this appeal what is the next step, release?
They received a 25 - 26 year sentence which if you read LondonJohn's comments (he is correct about the legal aspects) they are currently not serving. They are being held as flight risk/danger to society/whatever while they go through second level trial. If they lost this appeal they can go to the Supreme Court, following which they will be convicted under Italian law, but will nontheless be able to go to the EU. They would then get credit for time served.
Fruit loops Mignini, however, is also trying to appeal the first level trial, to go their sentence increased, no less. Go Guliano.

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