I am just a short trip down I-65 in Birmingham. BSL, is non-ABA, we have a similar attendance policy. Our mandatory hours of attendance are set by the Alabama Supreme Court. The reason the Supreme Court sets our class hours is that they have the power to grant or repeal our right to sit for the bar.
BSL, is pretty stict about classroom hours. The school doesn't want to screw up a good thing. I am sure there are a few people at UA and Cumberland who would like to see our exemption go away.
My legal writing instructor had a habit of ending class about 30 minutes early. The dean sent himn a nasty note and after that we started staying past the reqiured time.