Answered on October 29,2019
Normally, it takes around 6 to 21 working days to obtain income and caste certificates depending on the state you belong to. For example, as per the guidelines, you will get it in 6 days in Kerala whereas it will take up to 21 days in Karnataka.
There is no timeline specified specifically for the renewal of the certificate. For Income Certificate, it might remain the same as mentioned above, as you need to submit the latest payslips/tax returns. For Caste certificate, you will get it in lesser time as you can show the earlier caste certificate as proof of caste.