Sec. 5.05. PENSION SERVICE. (a) Subject to Subsection (d) of this section and except as provided by Subsection (e) of this section, a member shall receive pension service for the time, computed in years and fractional years for months and days, completed as a member of the combined pension plan, the old plan, Plan A, or Plan B.

(b) A member who elects to pay contributions for time spent on military leave, authorized non-uniformed leave of absence, or for an apprenticeship or probationary period, or for any other reason provided for by this article may receive pension service for the time for which the member is contributing only to the extent provided under Section 5.07(d), 5.08, or 5.09 of this article.

(c) If a member, either voluntarily or involuntarily, leaves active service and later returns to active service, the person shall receive full pension service for the period of the person's original membership, if the person did not withdraw the person's contributions pursuant to Section 4.04 of this article. If, however, the member had withdrawn the person's contributions and did not replace the previously withdrawn contributions as required by Section 4.04 of this article, the member forfeits any pension service attributable to any period of time for which the respective contributions were not repaid.

(d) If a member is assigned, for any period, to a job-sharing program or any similar work schedule that is considered by the member's department to be less than a full-time work schedule, the member's pension service is determined by multiplying the pension service that could have been earned for full-time work during the period by a fraction, the numerator of which is the number of hours the member actually worked during the period and the denominator of which is the number of hours the member would have worked during the period if the member had been working a full-time work schedule. This proration may not affect the computation of pension service for a member during any period the member is on leave:

(1) because of an illness or injury; or

(2) receiving periodic payments of workers' compensation.

(e) Notwithstanding any other provision in this section, a member may not receive pension service attributable to nonqualified service to the extent the pension service would result in either more than five years of permissive service attributable to nonqualified service being taken into account, or any permissive service being taken into account before the member has completed at least five years of active service. In this subsection, "permissive service" and "nonqualified service" have the meanings described by Section 415(n)(3) of the code.