Did we make a bad call in switching these exempt workers to nonexempt status?

Q: “We have a new HR Director. He moved four of our 10 management team members from exempt to nonexempt status. Two of those staff have the exact same title and job responsibilities a one member who he left exempt. He said that the one he left exempt worked on-site with the five people she supervises, while the other two only had two or three people they supervised and most of those supervised were at different locations than where the supervisors are placed. All four reclassified team members are responsible for coordination and oversight of component areas with expertise in those areas. When there are questions, they are the experts. This new situation has negatively impacted the team, and those staff now have to work diligently to not go over 40 hours. Can you clarify why they should not be exempt?” – Kimber, Kansas