How to interface open enrollment data to advanced benefits?

My client has handed over open enrollment efforts to an HR services company. They would basically work with all employees to gather all plan elections data and would give us a flat file at the end of open enrollment period to be loaded to advanced benefits.

What is the best way to load this data into EBS advanced benefits? Do you know anyone who has done this? What are the potential risks in this approach?

This HR services firm would only do open enrollment, any life event going forward will be handled in oracle advanced benefits.  We also use oracle payroll, so we need the benefit elections to carry over to payroll module for deductions.