This is concerning me too. If we get our fiance visa we will marry next July but our plan is just to have a quiet registry office wedding. We don't plan to have a reception, caterers, cars or any of the peripheral things many people have. I'm also going to book a honeymoon in the UK for straight after the wedding. Would the registry office booking, hotel reservation confirmation and a note explaining our plans and why thats the only proof we have be sufficient?