Hey @eroche.
I would think the review time is the moment at which the mod finishes their review and passes the post as meeting the requirements for the Utopian category. It's an intermediate step between - the Utopian bot wanders around and upvotes later once it's charged up - there can be quite a delay between the two.
Thank you for answering. Yes, review time is the intermediate step. Attempt to differentiate based on fields:
created)json_metadata.moderator.time)active_votes[utopian-io].timestamp)