Here are the links to the most popular reference articles for the famous “William and Kate” error sheetlets. The series include a discussion on “TRH” as well as the “Elizabeth” font – if it was an “x” or a “z”.
Part of the Royal Tour to the Pacific collection articles:
Solomon Islands: https://myfdc.me/2013/06/24/solomon-islands-royal-visit-stamps/
If you are interested in the items, send me an email at firstname.lastname@example.org