Non-equilibrium stationary states constitute a subject of increasing interest where computer simulation has proven to be an invaluable tool. In this paper we describe the behavior of a driven lattice gas when we impose shifted periodic boundary conditions, which are used in equilibrium to generate tilted interfaces. In the case of small shifts, our study shows a non-analyticity in the internal energy, in agreement with previous results which indicate that the driving field suppresses the interface roughness. When we increase the value of the shift beyond a critical angle, we first obtain a splitting into a multistrip configuration and then a series of merging transitions.