When an employee has a change in status, such as adding or subtracting dependents, or submits a new W-4 withholding form, you'll record that information and verify that the payroll system is updated. Filing is a large part of the job.
For instance, if a policy expired on January 1, 2007, the data included on the Experience modification would comprise the period from January 1, 2003 to January 1, 2006. Experience modifiers are normally recalculated for an employer annually. Each year, a newer year's data is added to the three-year window of experience used in the calculation, and the oldest year from the prior calculation is dropped off. The other two years worth of data in the rating window are also updated on an annual basis.
I am coming up on the 24th payment of my modification. My modification included a $160,000 principal reduction. It was through Bank of America. I am not sure if this makes a difference, but I am in California. I tried to refi a year ago but was told I had to wait until 2 years after the modification was complete. I was going through my paperwork trying to sort out the logistics of exactly when I can refi and when I can buy again, but I can't seem to find anything in my paperwork that says anything about 2 years or 24 months.