I attended yesterday's first day of issue ceremony of Cherry Blossom Centennial stamps (Se-tenant). I brought some older (1960 and 1966) single stamp depicting the same motif (correspondingly Washington monument and Jefferson's Memorial with Cherry Blossom!), affixed them on a pre-canceled silk cachet (for sale at USPS), and obtained the same postmark. I was one of very few collectors who went to the ceremony with self-prepared older stamps, and I enjoyed this interesting combinations. I just wanted to share the joy, and perhaps we will see more of similar kind of first day cancellation cachet here in this community.