The first thing that you need to understand about your Criminal Appeal is that you were only challenging the errors in the criminal process or in the application of the law. You will not get an automatic acquittal via an appeal and you are not automatically guaranteed a new trial. You may get an acquittal eventually if a new trial is ordered and if: 1. you then get acquitted in the trial; and 2. the Commonwealth (or State) decides not to prosecute you again. But a new trial is not guaranteed automatically because it depends on the basis of the appeal that you or lawyer filed.
There are three (3) results of an Appeal: 1. Affirmed: Where the reviewing court basically agrees with the result of the lower courts ruling(s); 2. Reversed: Where the reviewing court basically disagrees with the result of the lower courts ruling(s), and overturns their decision; 3. Remanded: Where the reviewing court sends the case back to the lower court.
If your Appeal is sent back to the lower courts you may get a new trial but also you may just get a new sentencing, for example, if that was the basis of your Appeal. Hence, what happens after your Appeal is granted all depends on the basis of your appeal.