Automatically change cell colours after 8 hours

Hello All

I need some help as I'm new to excel and have been told that this could be done

I have made a spread sheet at work that records people when they start work.
I write their name, start time and finish time on the spread sheet as they arrive.
I have approximately 140 staff every day and they all start and finish at various times of the day.
Staff also have various shift hours from 2 hours to 12 hours.

What I would like to happen is 1 hour prior to their shift finishes their name, row or finish time will change to red so it highlights that they will be finishing and then I could arrange cover to get then off without stopping production.

I put their name in column A, their start time in column B and their finish time in column C. I could add another column with the amount of hours they are working if it makes it easier.

If this could be done it would make my life a lot easier


Regards
Ian