I moved from Tennessee last year. I moved to North Carolina and finally got my NC permit. Now to answer your question -- Tennessee only issues resident permits and yes you will have to take the class again. You will also have to prove you are a resident of Tennessee when you apply for your permit. Your SC permit is honored by Tennessee by the way. So to make a long story short -- move to Tennessee, get your Tennessee drivers license then take the class, then go to the drivers license office and apply for you carry permit. It does not take a long time to get it IF you follow the instructions to the letter. Hope this helps...
While you're still a resident of SC, maybe you could see if TN allows its residents to carry on nonresident permits from other states. Since your SC permit is a resident permit you won't be able to do that with that particular permit. Get either a NH, PA, FL, or UT permit if TN allows that, and carry on one of those while you're waiting for your TN permit to arrive.