It looks like SDG-6 came down around 7:30pm tonight and - I think - it has been retrieved by someone!
I say this because around 8:20pm I received a cell phone call (which I could not take at the time - I was in the middle of the American Idol concert in Detroit) which appears to be from Cumberland County, Kentucky. While no message was left on my voicemail, this is very close (within a few miles) to where the last packet from the balloon originated - and my cell phone number was on the outside of the payload.
I will call the number back in the morning and then continue the story here.... This has been an amazing flight - over 32 hours in duration - and I have a feeling that the recovery story will be equally amazing!