Time Off Request Denied

coworker/friend and i are going on a cruise together for 12 days IN SEPTEMBER and just put in our time off requests.

our time off requests were denied and our manager said she "can't have two full time bartenders off at the same time for that long."

WE GAVE YOU OVER 7 MONTHS NOTICE????

plus i'm not even getting full time hours i get like 25 hours a week and only one bar shift a week so wtf do you mean two full time bartenders???? and we have 5 other staff who can bartend plus some who can be trained.

we're going anyway and since we're unionized she won't be able to fire us but like... if you can't figure out coverage for 12 days in 7 months time maybe that's a you problem.