I think a simlple way is to use Number.
First, I think we don’t need the year and the day ,we only need month.
So,there are two ways
- 0 >= date(today).month - birthday.month >= -2
- date(today).month - birthday.month >= 10 for Dec,Nov to Jan,Feb
You can use that in where and connect by “and” “or”.Maybe it’s easier to understand and maintenance.