This command appears on conference pages. It updates your records as if you had read through all the new responses and topics. If you've been away on vacation and there are fifty bazillion newresponse items from last week, maybe you'd like to just skip them and resume reading in the present. So use this command and you are current.
This command requires a confirmation, since it cannot be undone.
After catching up, you can also use the [Search] page or the [See Recent] shortcut to read just the last few days worth.