The interface date is a value which can be included in either the manual or automated transaction imports. Whether this value is optional or mandatory can be configured for you by Enable administrators.
Previously imported transactions can be removed through the use of interface dates. When automated imports are loaded into the system, the import will replace all transaction lines with an interface date between the start and end date of the import (the dates included in the file name). This is regardless of whether the initial transactions were imported manually or automatically.
However, whilst automatic imports have a default interface date set as the transaction date, this is not the case for manual imports. Therefore unless manual transaction lines have an interface date explicitly set they will not be deleted by automated imports.
This means that if you would like manual imported transactions to be replaced by automated imports, then they must contain an interface date value.
Please see our article on deleting transactions and turnover for more information, including how transactions can be removed from the system manually through the UI.