Let's say a user has an existing account upgrade. The normal term for the upgrade is a year, but this particular one is already six months old. The administrator wants to manually extend the user's term by an additional year. If you try to manually add an upgrade, the ACP just assigns a date a year out from *today*, and then overwrites the expiration date in the db, rather than finding the existing upgrade and adding a year to it. There are hundreds of current upgrades in the ACP>User Upgrades>Active list, and it's not searchable, so it's tough to find out when a particular account upgrade is set to expire. I usually just manually change the expiration date field in the db. Similarly, the account upgrade information isn't displayed in the ACP>Edit User page, so you can't view/edit it there.