Andy, I first learned of "obsoleting' notes quite a while ago. I used to make sure I had enough pounds in my pocket returning home to get me started on the next trip. With relatives there another trip is inevitable. So anyway it had been around four years when next I arrived in the UK. To celebrate I found myself in a nice old pub. Paid for my first round with a 5 pound note from the RB of Scotland. After a bit of inspection the publican said you know this is no good. I, of course, had no idea. He did decide it was interesting enough that he traded me the out of date bill for a pint. Not sure how that fits with the currency trader matrix but probably a poor rate of exchange. πΊ