2579992 - Multiple Hire Records allowed in employee's job history

I would like to ask about system behavior of handling hire record in Job History.   When I try to register multiple hire records for an employee via CSV import, system gives an error "A Hire record already exists for user {0}. You cannot import a Hire record twice using incremental import.".  However, when I try to register multiple hire record via UI, system does not give an error and I can save multiple hire records.

SuccessFactors

Employee Central 2.0

Multiple hire records insert in job history, EMPFILE_HRIS_IMPORT_INVALID_HIRE_RECORD_INCREMENTAL_IMPORT_DOUBLE=A Hire record already exists for user {0}. You cannot import a Hire record twice using incremental import. If you are trying to replace the existing Hire record, perform a Full Purge import , KBA , multiple hire records , hire record already exists for user , cannot import a hire record twice using , employee central , job history import , LOD-SF-EC-HIR , Hire & Rehire Wizards , LOD-SF-EC-JOB , Job Information , LOD-SF-EC-EDP , Import Employee Data (EC Core only) , How To