Abstract
We demonstrate that a straightforward limiting process can be used to continue trajectories in spacetime through exceptional regions in the velocity field (identified by Tumulka (2000 J. Phys. A: Math. Gen. 35 7691)) using the formalism we previously proposed (Horton G, Dewdney C and Nesteruk A 2000 J. Phys. A: Math. Gen. 33 7337).