Excel formula for color change and automatic Date Changes

I have an Excel worksheet in which I do scheduling and payments. So I have these two problems.
In my sheet I have 4 cells which display the date for the Mondays in a month. Example: 4 13 20 27
I have it so you had 7 days to the previous cell to get its date. What I am trying to figure out to do is 1: change the dates automatically when the month is done and two if the dates is more then 31 place an x in the cell.

Also under the dates is where I put the amount someone paid that week for 4 weeks.
If all the weeks are paid the first column in the row turns green, if not red. Then if they red, then name goes down to the bottom of the sheet.

I have been working on this but cannot seem to find the right way to have the results I would like.

Does anyone have any ideas? Please and Thank You

Also for the dates, They need to add an extra column if there is 5 mondays