Picking a list people randomly & evenly over a period in a calendar

Hi guys,

I have a query that hopefully someone can help with. I have a calendar where I want to pick 7 people and give them an even number of days in a month. I will probably do it over a 6 month period and ensure that everyone has an equal number of days.

I want to populate the yellow cells in the calendar with the people in the list, I am using the formula =INDIRECT(CONCATENATE("r",RANDBETWEEN(38,44))) and then pasting values (im sure this isn't the most efficient process) but I also then want to check the number of times the people appear in the list (column T for May for eg), just to ensure that no one is on the list too many times on a monthly basis).

Is there a formula driven method of doing this?

Thanks