A fantastic news for the morning.
Got response from HCI as below -
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Dear sir,
The OCI card is made on the basis of the British passport. however you need to include a the change of name deed affidavit along with the application for our reference.
Thanks & Regards,
Public Response Unit
High Commission of India
India House, Aldwych, WC2B 4NA
Tel: 020 7632 3070 / 020 7632 3170
Email:
info.london@hcilondon.in
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Thanks to all who contributed. After naturalisation, we will execute a deed poll to change surname and then apply for British passport with Birth certificate, Naturalisation certificate and Deed Poll. OCI should not be a problem then, with above confirmation.