The review process for all published content is part of our 8.5 release. All public content published to our browse directory must now be reviewed before it is published.
Being under review should not affect the bot at all, it should still function normally. It will just be hidden from our browse directory. If you are signed in as your own account you will still see the bot. Anyone with the bot's direct link will still be able to chat with the bot. Also if you set the content filter to "Mature" you will still be able to see bots that under review.
Are you seeing any issue in chatting with the bot, or just cannot see if when not signed in?