I am OCI and have never been fingerprinted---most recent entry was through DEL (Dec 2022). It is not at all clear to me what triggers fingerprinting.

In DEL I did use the normal foreigner line but it was quick. It was nice of them to offer a separate OCI counter in the past (and possibly in future), but there is certainly no requirement that they do so. We are foreigners and can reasonably be required to use the foreigners' line.
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