(a) The amount of the monthly service or disability pension payable to a former employee shall be computed in accordance with the provisions of § 5527(a)-(f) of this title except that 5 years shall be added to the former employee's credited service for purposes of calculating the amount of the monthly pension.
(b) The amount of monthly pension payable to a former employee for the first 3 months of retirement shall be double the amount calculated in subsection (a) of this section, but in no case shall such amount exceed 100% of the former employee's final compensation in the last month of actual employment. Thereafter, the monthly pension payable shall be the amount calculated pursuant to subsection (a) of this section.
(c) Individuals eligible for the early retirement option and whose pensions are effective prior to the dates specified in § 5301(d) of this title shall have their pensions computed in accordance with the provisions of § 5527(a)-(f) of this title without taking into consideration subsections (a) and (b) of this section until such time as they would have terminated in accordance with § 5301(d) of this title. Then, beginning with the month that their pensions would have been effective had they terminated in accordance with § 5301(d) of this title, their pensions shall be adjusted in accordance with subsections (a) and (b) of this section.