shift schedule

Hi, I am trying to make a Saturday to Friday excel sheet for a deli schedule and make sure I have coverage along with giving days off.
Here are the shifts I am trying to use for a 5 day work week for each employee sometimes they need extra days off so that is why I put primary, secondary and optional
5am-2pm primary
6am-3pm secondary
9am-6pm optional
10am-7pm primary
12pm-9pm secondary
2pm-11pm secondary
2pm-11pm primary
2pm-11pm primary

I have 10 employees.
will later have 15 employees and more hours to give during the holidays so I need to have room to grow in the excel sheet

thanks
I need a formula to move the schedule around when a shift is replaced or a formula with a drop down with all the available shifts left for that day
I think what I am looking for is a addin that would have all the choices for each day but I am not sure how it would cross reference across and down

What is the question?