They don't seem to bother when in civil partnerships; Mr Furness is not known as Mr John, for example; so the question is not likely to arise when the partnership and marriage ceremony is called a marriage instead.
Nothing in the marriage service amounts to 'you are now Mr and Mrs Smith' when Miss Jones marries Mr Smith, and there is no law requiring that. My wife called herself Mrs [professional name] and that name was not even her maiden name. She used Mrs Puli only for some government documents, to avoid some jobsworth or civil servant being confused.