The book calls for 8 1/2 quarts - but if you putin 8 1/2, you get the hi oil alarm a lot.
My last car, I drove for 73,000 miles on 8 quarts - never saw the alarm.

If the dipstick shows that it is essentially OK, I'd not worry about it, but at the next change make it clear that they are to use only 8 quarts.