I would think it should be obvious, as to the reason why Jeremy's comments have become transformed, from "She has", to "Sheila has", because of the earlier call made to police by Ralph Bamber, since in that call (3.26am), Ralph makes mention of his daughter - so that by the time Jeremy makes his own call (3.36am) to police, introducing himself as Mr Jeremy Bamber, police interpret what Jeremy told them differently...