Ahh what joy. My wife and I first saw G-PBYA over White Waltham in July 2005. It prompted us to go an see it at Duxford, where I took this pic:
http://www.brendan-mccartney.fotopic.net/p31507591.html
We later extablished contact with the New Zealand Catalina group and had a flight on their machine earlier this year. Truly a fantastic aeroplane.