‘The moment Jesus knew that the time had come’ (John 12:20-36)

Just before the events of Good Friday, John records an event in the life of Jesus when Greek men came and sought him out. The arrival of these men has a trigger for Jesus that the ‘hour’ had come, that the cross was near, but what did the arrival of these men signify?  What was John saying about what was before Jesus? And, was it ‘all over’ once that has taken place?