This comment is created automatically whenever a new membership is opened, and is given a purge date according your configuration settings.  You can access the comment and change its purge date, or delete it entirely, via Tool #70 Enter General Member Comments/Messages.  This comment is not connected in any way to the open date on the actual membership account, so it is not affected by changes made to that date.

Note: This comment is activated via Tool #551 New/Closed Reason Codes/Comments Config.  You can activate the feature or not, and set the default # of months used to calculate the comment purge date.