With further investigation, there might be coloration between SLC (Self Loading Cargo) and GSX operations.
"I think he means that the bus/van arrives near the plane and nobody gets off the van. Something similar happened to me as well but when using SLC in conjunction with GSX. The crew bus would arrive with open doors and nobody would come out. However, I've seen them come on foot, walking towards the airplane from where the crew bus initially spawned. Unfortunately, even when they finally got on the plane, the crew bus remained near the plane never leaving and blocking the rest of the boarding process. In my case the plane was the PMDG 737."
