a) Adult division. Every person serving one or more indeterminate terms of imprisonment for felony charges in the custody of the Department of Corrections shall be eligible for parole when he has served:

1. 1) the minimum term or terms of indeterminate sentences, less "good time" or 20 years, less "good time," whichever is less, or
2. 2) twenty years of a life sentence imposed prior to the law in effect on February 1, 1978, less "good time," or
3. 3) one-third of a definite sentence imposed prior to January 1, 1962, less "good time," or 20 years less "good time," whichever is less.
4. 4) In each case, "good time" shall be deducted as prescribed by the regulations of the Department of Corrections, providing for the diminution of sentences as required by statute.

5. 5)

   1. A) Persons sentenced or adjudicated under the provisions of the Unified Code of Corrections in effect January 1, 1973, but prior to February 1, 1978, if not sooner released on parole shall be granted parole according to the following schedule:

      1. i) A person who has served his maximum term of imprisonment, less "good time" shall be released to serve the statutorily prescribed period of parole.
      2. ii) A first offender under the Juvenile Court Act (Ill. Rev. Stat. 1981, ch. 37, pars. 701-1 et seq.) shall be released on parole on or before his 20^th birthday.
   2. B) Persons sentenced or adjudicated under the law in effect on and after February 1, 1978, or who have accepted release dates set by the Board in accordance with prescribed procedure shall be released on their release dates provided they agree in writing to accept conditions or such other sanctions as prescribed by the Board.
6. 6) Indeterminate consecutive sentences which may be aggregated will be treated as one long sentence for purposes of parole eligibility. Such persons will be eligible for parole when they have served 20 years less "good time" or sooner according to the schedule set forth above.