SWT 159013 - Chichester to Brighton - 6.8.2014

I think that this service originated at Bristol - we got on at Chichester. I always like seeing trains that don't belong to the local train company, but this was better as a South West Trains 159 was providing a First Great Western service on the Southern's territory! I don't know whether this is a regular working or if it had to be borrowed in an emergency.