You can only upload rates that are effective immediately or for the future
Since billing is done in real time, calls are billed immediately and an xDR is written to the database. In order to modify xDRs that are already in the database, a re-feed should be used. Therefore, when you are copying a rate entry between tariffs that include the Effective from column with a date from the past, PortaBilling adds/updates this rate entry as effective immediately (if the appropriate check box is selected, otherwise these rates are skipped). This protects the integrity of the data and ensures that updated rates will be used to charge end users for new calls only.
You can schedule the discontinuation of a rate
It is possible to schedule a rate for a certain prefix to be discontinued on a given date in the future. This simplifies the management of the vendor’s tariffs since an announcement that a rate for a prefix is no longer available is typically received in advance. If you perform the upload immediately after receiving the updated rate sheet, the system will continue using the current rate for that prefix until the moment it actually becomes inactive (the date and time specified in the Effective from the field).