of Prisons shall, to the extent practicable, provide that increasingly less restrictive conditions shall be imposed on prisoners who demonstrate continued compliance with the conditions of such prerelease custody, so as to most effectively prepare such prisoners for reentry. (5) Violations of conditions If a prisoner violates a condition of the prisoner’s prerelease custody, the Director of the Bureau of Prisons may impose such additional conditions on the prisoner’s prerelease custody as the Director of the Bureau of Prisons determines appropriate, or revoke the prisoner’s prerelease custody and require the prisoner to serve the remainder of the term of imprisonment to which the prisoner was sentenced, or any portion thereof, in prison. (6) Issuance of guidelines The Attorney General, in consultation with the Assistant Director for the Office of Probation and Pretrial Services, shall issue guidelines for use by the Bureau of Prisons in determining— (A) the appropriate type of prerelease custody or supervised release and level of supervision for a prisoner placed on prerelease custody pursuant to this subsection