A news feed announcement will send a noisy push notification to your lock screen when posted.

An announcement will be marked by an animated icon, which will continue to present itself until you dismiss the notification. Dismissing the icon is an acknowledgement that you have received the important updated posted.

Click the animated icon to dismiss, and head to the announcements header if you need to refer back to individual updates.

Reacting to, or commenting on the announcement post will also act as an acknowledgement and dismiss the orange animated icon.