Conservation of the Newman-Penrose Conserved Quantities

Using an example of Press and Bardeen, Newman-Penrose quantities of the electromagnetic field in a Schwarzschild background are related to a differential conservation law and hence changes result from a flux. There is no discontinuity in the quantities resulting from a sudden change in dipole moment; there is no singular surface which moves out at 1/3 the speed of light. It is suggested that for Newman-Penrose quantities to exist, multipole moments must approach a limit as 1/u, u→-∞.