We had Informed Delivery at our old house, and now we have it at our new house... except we don't know how to stop receiving emails from the old house, so we know what the homeowner of our old house gets every day.
Did you setup a different email account for your new house ? I think they have some very simple check (not that secure obviously) that a single email can only sign up for informed delivery for one address.
There's a link at the bottom of every email to unsubscribe