What will be basis for calculation of PF pension in case of an employee continues service after the age of 58 years?

What will be basis for calculation of PF pension in case of an employee continues service and continues to contribute to PF after the age of 58 years. average of 60 months preceding the day he completes 58 years or average of 60 months from the last salary

I have worked in apsrtc since 1981 and retired on 28.02.18. my basic as on 1995 is more than 2500 and basic as on retirement is above 15000. Recently my pension was fixed as 3131. As per pop my pensionable salary 12310 service 22 years bonus 2 years and non pensionable service 24 days before 1995 only. As per above calculation i will get 4300 for the service rendered after 1995. Pl calculate correct pension and intimate with calculation