Once my CV didn't look 'empty' without school/university, I took them off. So, school came off my CV around halfway through my sophomore year, and then university shows came off my CV about a year after graduating - while still leaving my degree on!
This seems to tie in with what you hear, but it's purely coincidence. I have classmates who took their uni shows off earlier, or later, depending on the number of professional credits they had.
C