Brian, thank you for your patience. Although I've flew in stand-by through Brazil and South America, this is my first non-rev international trip and, as you can see, I don't know nothing about airlines like Delta.

Answering your question: Yes. Until now, the only agreement is with Delta.

I hope I'm not being insistent, but would you risk a guess if my chances are higher at ATL or JFK? I'm thinking to travel around January 9th or 10th.