A direction under section 31U has binding effect from the time it is made until the witness in relation to whom it applies is discharged.
But the court may revoke a direction under section 31U before the witness is discharged, if it appears to the court to be in the interests of justice to do so, either—
The court may revoke a direction under section 31U on an application made by a party to the proceedings only if there has been a material change of circumstances since—
The court must state its reasons for—