Using OTBI to fetch latest ACTIVE assignment

We would like to use a filter which we can re-use to fetch the latest active assignment for a person.

For 99% of our population, it works to do MAX("Worker"."Assignment Number" BY "Worker"."Person Number"). However, for one of our workers it's not giving the correct result. This case is a bit exotic, because the worker has had multiple global transfers and a split assignment/payroll. He now returned to his original assignment (the split assignment is changed back from 0.1 to 1.0 FTE) and the 'newer' assignment was terminated.

I found this topic, but I got the same result from that setup.