Finally, I have my GA for San Diego! I called the U2.com 800 support phone number TM originally gave me. After a 15-20 minute hold, the woman I spoke to gave me a different number to call regarding presale code issues, 1-855-867-5297. The hold time was less than 15 minutes. The guy I spoke to was able to get me a new presale code and even stayed on the phone while I went onto TM.com to try to purchase the ticket. I was able to unlock the Red Hill presale no problem and purchase my GA. I'm happy! What a long ordeal that was, but happy I finally "found what I'm looking for".