YouTube Premium afterparties are Premium-exclusive live streams with artists. They're an opportunity for YouTube Premium and YouTube Music Premium members to engage in real time with artists who host a video feed and live chat. Premium afterparties are available in all markets where YouTube Premium and YouTube Music Premium are launched.
Live chat messages and comments on YouTube Premium afterparties are visible to all YouTube Premium and YouTube Music Premium members who access the live stream. This means live chat messages and comments on these live streams may be accessible to all current and future YouTube Premium and YouTube Music Premium members who can view the archived live streams.
You can still view your own live chat messages and have the option of deleting them by visiting your live chat history, even if you're no longer a YouTube Premium or YouTube Music Premium member. You can also view your own comments and can delete them by visiting your comment history, even if you no longer have YouTube Premium or YouTube Music Premium.