I have not crossed the 50yr mark but here are some points to the questions in this thread:
- Surrender of Indian passport is a must before you can avail any service from the consulate - so even for multiple entry visa, you must first surrender your Indian passport.
- OCI gives parity with NRI. The only restrictions are on agricultural properties. In my view it should not affect other properties
- I did both surrender and OCI application at same - i used BLS toronto and opted for courier services - they shipped docs back via Fedex and i had no issues
- Things have changed from the past and you don't have to keep renewing your OCI booklet everytime you get a new passport. From the CGI Toronto consulate site:
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1. The OCI card is required to be got reissued each time a new passport is issued to the applicant up to the age of 20 years and once after completing 50 years of age in view of biological changes in the face of the applicant. (However, in emergency cases, the applicant can perform the journey and apply for OCI renewal upon his/her return).
2. Reissuance of OCI card is not mandatory each time new passport is issued between 21 and 50 years of age. However, if applicant wishes to avail this service, he/she can apply for the same.
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Also from the Indian MEA site:
For an applicant who is 50 years of age or older, OCI documents must be re-issued once after the issuance of a new passport. (If the OCI card is issued for the first time after the age of 50 years, then there is no need for re-issuance of OCI.)
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So BLS Toronto answer is right - the first time the Canadian passport is reissued after crossing 50 years, that is the time to renew the OCI card.