Formula to format cell color based on time ranges (not dates)

In this example, with the employee start time at 8:30, she is early so there wouldn't be any penalty points accrued. If she punched in at 8:45, she would have 4 points accrued. 

I'm reviewing the point structure with my supervisor but it may be:

0 to 3 minutes grace time.

4 minutes to 8 minutes = 1 point.

9 minutes to 12 minutes = 2 points.

13 minutes to 15 minutes = 3 points.

Over 16 minutes = 4 points. 

Employee start and end times vary so I would enter these in separate columns on the first line of each employee.

Thanks.

Thank you for reviewing my question. 

My goal is to have Excel "judge" how late after the employee's start time he/she punched in. In the example, she punched in one minute early at 8:29. Other times she punched in late. Moreover, she punched out early at 1:00 rather than at 1:30, the time her shift ends. I hope this makes sense.