a) Parolees shall be under the continuous supervision of the Division of Parole Services of the Department of Corrections according to the following schedule:

1. 1) Persons sentenced or adjudicated under statutes existing prior to January 1, 1973, shall be on parole until the expiration of the maximum periods of their sentences subject, however, to earlier discharge under paragraph (3).

2. 2) Persons sentenced or adjudicated under the provisions of the Unified Code of Corrections prior to February 1, 1978, shall be on parole as follows, subject, however, to earlier discharge under paragraph (3):

   1. A) For murder or a Class X felony, 3 years.
   2. B) For a Class 1 or 2 felony, 2 years.
   3. C) For a Class 3 or 4 felony, 1 year.
3. 3) The Prisoner Review Board may enter an order releasing and discharging a parolee or mandatory supervised releasee from supervision (with court approval for juveniles) and his commitment to the Department when it determines that he is likely to remain at liberty without committing another offense.
4. 4) Issuance of a discharge by the Board shall be within the discretion of the Board and shall be conditioned upon the favorable recommendation of the Office of Parole Services, based on the parolee's or mandatory supervised releasee's faithful conformance to the terms of his parole agreement. In extraordinary circumstances and on the recommendation of the Office of Parole Services the Board may, in its discretion, grant a final discharge at an earlier date.
5. 5) The order of discharge for adults shall become effective upon entry of an order of the Board. When approved by the Governor, said order shall operate as a commutation of sentence. The Board shall notify the clerk of the committing court of the order.

d) Parole to warrant or detainer

1. 1) The Board, in its discretion, may parole an applicant to a warrant or detainer to serve his parole concurrently with another sentence. A condition of such parole may be that if the charge or charges on which the warrant or detainer is based are dismissed or satisfied prior to the expiration of his Illinois parole, the person shall be returned to Illinois to serve the remainder of his parole under the supervision of the Illinois Parole Services Division unless the Board, in its discretion, orders that he be permitted to serve the remainder of his parole outside of Illinois or that he be discharged from parole.
2. 2) If a person paroled to a warrant or detainer is sentenced to probation, or released on parole in another jurisdiction prior to the expiration of his Illinois parole, he shall serve his parole concurrently with his probation or parole in the other jurisdiction or in Illinois as ordered by the Board.