There used to be, and quite possibly still is(I'm just not finding all of it right now), an EXTREMELY KNOWLEDGEABLE resupply article here on WB written by Jack Tarlin aka Baltimore Jack concerning resupply pts and the pros/cons of buying along the way versus mailing. Read it! It's written by someone who quite probably knows more about resupplying on a AT thru-hike or section hike than anyone else alive. At least LISTEN and STRONGLY CONSIDER what Baltimore Jack says in regards to AT thru-hiking. You might say he has a little worthwhile experience as a AT hiker!