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I've just typed Bridlington Registry Office into the search bar and up it came. A whole section on it, plus a list of registry offices in the country. It appears that there are several correct ways of referring to this office including Registration, Register etc., so everyone should be happy. :)
If I can get the gilding on the deckle-edged slate slabs done and delivered on time, your invitations will all be sent from China on the swiftest cargo-steamer available. Thanks again everyone.
The woman on the phone was still being awkward when they rang again on Friday, so our friends informed her that it was just 7 days residency and what paperwork they needed. She said they were wrong, they said they had legal advice! Anyway they got an appointment with the actual registrar who is quite happy that they qualified legally.