We just finished our new pool and had "upgraded" the deep end from 8 feet to 9 feet deep. But now that it's finished the deep end is "only" 8'7" at best. I measured with a PVC pipe that I marked with inches.
Given our spa over flow, the waterline can not be increased any further.
How accurate is your pool depth? When you paid for X feet deep, did you get X feet deep?