Hello,
If your OBC-NCL certificate is valid, issued after April 1st, digitally signed, has a QR code, and mentions all the required details, then there should not be any problem.
Even if the format is slightly different, the main thing is that it proves your OBC-NCL status under the central list. Also, since the IISER help desk has confirmed that uploading a valid document before the deadline is fine, your reservation is not likely to be cancelled.
Hope it helps !
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