Customers working with the FULFILLMENT CENTER who are attempting to insert a new column into the grid (GRID + INSERT COLUMN) for the purpose of balancing a large number of documents to be printed over a series of days have had issues trying to insert a column that has a date that is older then any displayed in Fulfillment Center.
The GRID + INSERT COLUMN will only allow you to insert dates that are past the oldest date displayed in the Fulfillment Center grid. If you want to balance to an older date you would need to open WINSALES and find a scheduled letter and manually change the date back to the older date value that upon reopening Fulfillment Center would display allowing you to balance.
For example in the below screenshot of the Fulfillment Center grid users could not insert a column before the date 9/23/03 as that is the oldest date displayed in the grid. Any date beyond 9/23/03 can be inserted.