Although GTR Thameslink services to Brighton are now diagrammed for Classes 377 and 387, Class 319 units still occasionally reach the coast. Also, as this picture illustrates, still run the diversionary route via Lewes. Here 319421 passes north through Lewes station on 28th March 2015 on a driver training (route learning/refreshing) run between Brighton and Gatwick Airport.
photograph by Chris Livings