It almost seems to me like the 12th should be dissolved entirely and relocated. There's a lot of population loss in South Georgia.
Have you tried to do this? I wonder what the outcome would be. 1+2+8+12 = almost exactly four districts at the current target, but I could see moving some of the 8th's northern territory into an Atlanta exurban district and having it and the 10th take up much of what remains in 12 while moving the rest of Savannah in to the 1st. Paul Broun and Austin Scott wouldn't be reps for life, but it could be safe enough.
