Expansion of initials in birth certificate

You should have a notarized Affidavit mentioning the reasons for change/expansion of initials. secondly get it published in a leading local news Paper. 3rdly it shoul be published in official Gazette.

What about your school/college and any other government-issued IDs/records? Does any one of them have your parent's surname with all other particulars, viz., your name in full(including surname), dob, etc., tallying? If so, simply add those documents to your  application form as supporting documents;, explain to them the omission of surname at the time of getting your dob certificate. Most probably, the authorities will accept it. Otherwise, you have to go to your dob certificate-issuing office and get it re-issued by enclosing necessary proof.

The birth certificate was once mandatory for Passport requirement.  Now that Central Government has directed authorities to accept DOB etc., as per qualification certificates, BC lost it's value.

If the full name is registered with authorities at the time of Birth registration, a simple applciation for modification, (with a sworn affidavit duly notarized with supporting copies of certificates)  before Registarar of Births is enough for getting revised DOB certificate.  There are fees prescribed for such modification.

At the cost of repetition, there is no such additional value for going into such modification, when that is not material in any way.

Birth certificates do not generally give initials of the person. It will give gender, just name, if reported, and full names of father and mother. As father's name will be there in the birth certificate, one can use it in full form or in abbreviated form. Generally alterations in the birth registry are not permitted beyond a certain period. What we call birth certificate is just true extract of the entry in the birth registry. Even spelling changes are not allowed in the original register. As regards other date of birth records, experts have given advice.