I went to their website and it says that they have a contract with Delaware, and other states, but I couldn't find anything about not accepting students from other states.
From when I was looking at schools to apply to, I saw they've accepted all of about 2 OOS students in the past 3 classes. Those are some pretty rough odds!
They admit up to 10 students from other states. Most of the accepted students also get accepted to their in-state or preferred schools so the number admitted is usually low. I wouldn't think that it's impossible, but if you're not likely to get into your state school, you're not likely to get into UGA OOS.