Formulas to help split a month into weeks (mon-sun)

Hello,

I am working on a monthly revenue tracker for our sales department and trying to automate a few calculations. In the attached workbook, I have a cell for them to input the first day of the month, C9, which will always be the 1st. I have have cell that captures EOMONTH, Q9. Most months are going to have 5 total "weeks" with either the first or last week being a partial week. For the life of me, I cant figure out how to split each month accurately in Row 9. For example, October 2018 starts with a Monday and Row 8 accurately records the day of the week. How do I make this work? The week always needs to start on MON and end on SUN UNLESS, it is the first or last week of the month....

I hope this makes sense. Working with dates/serial numbers is tricky for me.....