Coach cannot keep track of time

I love most of our coaches. But we have one coach who will keep us an extra 15-30 seconds on an incline, or cut an all out short by 30 seconds. I determine my level of effort based on how much time I’ll be in that phase, so it can be really irritating. I am trying to avoid her classes, but that is not always possible. Should I say something to her or the manager? I don’t want to come across as a Karen, but I can’t be the only one bothered by this can I?

Update: I decided to mention to the studio manager, who is very kind, understanding and approachable. She thanked me for the feedback, and said that was not the first time they have received that feedback. After that, the coach in question was on the calendar for another week or so. She was teaching a class in a Sunday where there were two other coaches taking the class. She had several misses on timing in that class. I don’t know if it is a coincidence or not, but I haven’t seen her on the schedule since.