Unless you are a catechumen, you don't "depart". You get to stick around. I know this from experience.Honestly Catechumens don't even "depart" anymore.
This is one of those practices, such as subdeacons kissing the bishop's hands after washing them, or taking the blessed water to the people at the Great Entrance, or a number of other practices, where some people like to say with absolute certainty, 'This doesn't happen anymore', but you can be guaranteed that there will be a number of places where it does
A mere five years ago, my fellow catechumen and I were expect to leave at the dismissal of the catechumens. We would take the time to discuss our faith journeys with each other, what we had learnt and how we had progressed, then we would be allowed back in after the Litany of Thanksgiving. This is the custom of my parish and is what my priest was taught to do by the archimandrite who instructed him. I would be very surprised if this custom were hard to come by.