Apologies for the delay in responding but I have been away and just checked my email today. I'm happy to answer your questions and grateful for the brilliant blog which keeps me posted on PR all the time (unfortunately, we can't see the show here in the UK.)
The producers rang me a week before filming but nothing was confirmed until the night before my flight. I traveled alone. I lived in New York for 11 years so it is a familiar city. I spent my free time visiting with friends who had no idea why I was in town on such short notice.