Overturning a conviction is usually permanent, however, that does not necessarily mean the verdict becomes Not Guilty, and only when the verdict is Not Guilty does double jeopardy come into play. It is possible for a higher court to overturn a lower courts decision, have it returned for reconsideration, or even a whole retrial. In other cases a higher court will overturn a verdict and instruct the lower court the change the verdict to Not Guilty.