Here's a funny thing. Last year this website featured a short article about the "Hark the Herald Angels" GB Christmas miniature sheet, with its reference to Charles Wesley. It's now been brought to my notice that the illustration in that piece, used in Royal Mail pre-issue publicity, was wrong. If you look at the FDC pictured here, you'll see that the 69p value at the top right was replaced in the issued sheet with a 78p stamp. An example of very fast inflation in stamp prices?