For morning unit PT every unit I was ever in always ran on Monday, Wednesday, and Friday and it would always be 4-6 miles. On days when we would do ability groups I would always be in the fast group and we would usually knock out 10 while the slower groups would still do 4-6.
Personally I would run on my own every night, even on days I ran with the unit and would usually do 8-10 miles after dinner.