We at LO do sign it. We have a diagram each day where we are ECS from West Croydon, in to the loop, shunt back across to the Down Sussex Slow, through NXG and then change ends, shunt back down through Platform 1 in to the depot.
There has been a few occasions of engineering work where there is no service north of NXG, we terminate platform 5, in to the Up Sussex Loop then back to use Platform 2.