It depends on why it closes.
Planned, for repairs or works. The owner tells us ahead, for some spots or the whole staging area. Nobody is asked to leave: a vehicle is never given a spot, or a stay, that runs into the closure.
Sudden, by the police or for a fire. The whole staging area closes at once, and every vehicle there has to go. We tell you straight away, with other staging areas nearby that have room.
More in When a staging area closes.