Flow - day of month 1 less than variable

Solved by setting today’s day of the month as variable with homey script and then use logic flow card to to the rest.

Hi

what’s the simplest way to use day of month 1 less than a variable.

let’s say the variable is day 12 of the month and i want the flow to execute 1 day before. (11)

or define current day of month with homey script