(4)__Section 18451, which governs participating local district regular plans;

(5)__Section 18453, which governs participating local district special plans; or

(6)__The terms of a retirement plan provided to employees pursuant to section 18252-B.

B.__For purposes of this subsection, "time of vesting" means, for each employee, the date on which that employee met the creditable service requirement for eligibility to receive a retirement benefit, at the applicable age if so required, as set forth in paragraph A, subparagraphs (1) to (6).

C.__The State makes solemn contractual commitments under this subsection that, with respect to any group health plan offered by the State:

(1)__Eligibility criteria for a vested employee or a family member of a vested employee to participate in a group health plan under this section after retirement will be no more restrictive than eligibility criteria applicable to that employee or family member at the time of vesting;

(2)__The state contribution toward the cost of the premium for any group health plan offered by the State for a retired vested employee, as a percentage of the cost of coverage, is not less than that provided at the time of vesting; and

(3)__The group health plans offered in each plan year to retired vested employees under this section will be the same as or substantially similar to the group health plans offered to active employees in that same plan year.__The State Employee Health Commission shall determine whether plans are substantially similar.

D.__This subsection does not create a contractual commitment on the part of the State to offer group health plans or to maintain coverage for a specific type of benefit or level of benefit payment.__The State may reduce or eliminate coverage for types of benefits or levels of benefit payments for