This is a subject that crops up in various periodicals from time to time, two of them having mentioned an instance amongst my relations. When the phenomenon occurs, there is often a military connexion, and it has been suggested that there was an omission on the part of the soldier to get his C.O's permission for the earlier ceremony. I am not sure that anyone has found confirmation of this explanation, but no-one seems to have come up with a better one. My relations went through the first ceremony in a parish church, and the second at a register office. Jeremy Wilkes