Delegate - The user selected in the next field will be granted the authority to take workflow actions on behalf of the user selected at the top of the dialog for a period of time. The original user will still be able to take workflow actions during this time as well (The first action taken by either user - original or delegate - will be the one that counts.). Delegations can be activated and deactivated whenever desired.
Replace - The user selected in the next field will permanently replace the user selected at the top of the dialog in all selected roles. The original user will no longer be able to take workflow actions based on those roles.
Both - This is the default. The action applies to both current and future records.
Current - The action applies only to records that have already been submitted into workflow at the time the line is activated.
Future - The action applies both to records that have already been submitted into workflow at the time the line is activated as well as records subsequently submitted up until the moment that the line is deactivated.
This field is only available if the selected action is "delegate". If a date is selected here the delegation will automatically end on that date, without user intervention. If this field is left empty the delegation can be manually ended at any time by deactivating the line in this dialog.