I'm way out of my depth and and not even sure if a macro like this is reasonable (I'm sure it's possible, it just may be more effort than it's worth).
I have a series of days in column "A" (starting in row 3), 1, 4, 7, 3, 5, 22, 4, 8, 30, etc. The numbers are the day of the month.
In Column...