Effective dating
The effective start and end dates in the OVR_START_DATE and OVR_END_DATE fields (columns 1 and 2) are mandatory and must be placed in column 1/A and 2/B respectively.
If the import value for OVR_START_DATE is empty, the default is the current system date. If the import value for OVR_END_DATE is empty, the default is 01/01/3000.