When must a car rental be returned after the car is repaired?

My policy allows up to $30.00 per day to a maximum of 30 days while my car is being repaired. When the car becomes drivable, then I return the rental vehicle and retrieve my car. The rental can not be kept for longer than it takes the car to be repaired and drivable. So I am curious from anyone’s experience, what is the reasonable time to return the rental vehicle and then retrieve the repaired car? I ask because I was notified that my car was ready at 3:30PM, and I returned my rental at 7:30 the very next morning. I could not pick up car by 5PM because I was working in different town. I have tried to contact my insurance company but they will not say 24 hours or eight or whatever. I am now being charged from the rental car company for that next day. I assume the charge is being placed because the insurance company thinks I could retrieve my repaired car by 5PM. Anyone have ideas or experience?
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