An inmate who is serving a sentence of imprisonment who is not eligible for presumptive parole pursuant to section 501a of this title shall be eligible for parole consideration as follows:
(1) If the inmate’s sentence has no minimum term or a zero minimum term, the inmate shall be eligible for parole consideration within 12 months after commitment to a correctional facility.
(2) If the inmate’s sentence has a minimum term, the inmate shall be eligible for parole consideration after the inmate has served the minimum term of the sentence.