Alert when billing overlaps

Would be great if there was an alert when two staff are billing the same code at the same time. For example, a session with one therapist ends at 1:00 and the next therapist takes over, but the first therapist accidentally has her end time for 2:00 instead of 1:00. It would be great for WebABA to alert saying we have the same code on the schedule for two different therapists from 1:00-2:00.