Aggregation in 2001 but not in 2002 . . . what are the prior year NHCE

[Guest T-BONE]

Two plans (A&B) are permissively aggregated in 2001. The test is performed by excluding all employees who do not meet the statutory minimums. For 2002, plans A&B are tested separately. Plan A uses prior year data, Plan B is now safe harbor (deemed to be using current year data). How do I determine my prior year NHCE averages under plan A? Do I use the prior year averages of the aggregated plans, or do I need to re-run the 2001 test just to determine what the prior year averages would have been for plan A if it were tested separately in 2001?