Such annuitant is not entitled to a recomputation of his or her retirement annuity unless at least one full year of creditable service is rendered after the latest re-entry into service and the annuitant must have rendered at least 3 years of creditable service after last re-entry into service to qualify for a recomputation of the retirement annuity based on amendments enacted while in receipt of a retirement annuity, except when retirement was due to disability.
However, regardless of age, an annuitant in receipt of a retirement annuity may be given temporary employment by a school board not exceeding that permitted under Section 16-118 and continue to receive the retirement annuity.
40 ILCS 5/16-150