There's nothing special about the BTP prefix. It's a slightly older prefix printed in 2007, and consequently, it probably feels kind of weird to get brand new ones at this point, but it's still nothing special. Coincidently, I just came across some brand new $5 AOR notes printed in 2006! However, I think we will be seeing more and more older prefixes hitting circulation in the next 12 months as many institutions (banks and others) will be reaching deeper into their vaults. They will be receiving fewer newer notes from the Bank of Canada as production of the Journey series winds down ahead of the proposed launch of a new series of polymer notes in 2011 or 2012. So this could be an interesting time to be a collector.