On 17th October I have sent a long letter to the Prince and Princess of Wales with my address at the end just in case - I was aware they don't sign, so of course I was hoping for just a response and not an autograph (but still calling it half success as we're mostly here for signatures). I also live in the UK, so I thought my taxes should be enough for them to pay themselves for postage if they wish to respond.
Yesterday (6th November) I received a letter from the Head of Royal Correspondence at Kensington Palace with an attached non-signed photo of the royal couple.
The address I have used:
Their Royal Highnesses The Prince and Princess of Wales
Kensington Palace
London
W8 4PU
Photos:
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Great Success 
