The "one day off a month" means literally, one day of not working per month, not one day of vacation time per month.
After one year of service, the median is in 10-14 day range for vacation; the majority get 10 days or more, and only 39% get less. And this gets better with longer service.
https://www.bls.gov/ebs/factsheets/paid-vacations.htm
The "one day off a month" means literally, one day of not working per month, not one day of vacation time per month.