In the United States, WHEN she/he is working on a "reserve/on call" basis, usually after the end of a trip, a FA calls "crew scheduling" to confirm that she is off duty and no longer needed for the day...this may be done with a live person or an automated system. when a FA works on a 'schedule',they usually dont need to "call out" after a trip Days on/off are known a month in advance. Usually a FA with seniority has a "schedule" that she has bid for and been awarded...usually a few days clustered at a time, such as: a four day trip, one day off, a two day trip, four days off, a one day "turn-around", another four day trip, and then two weeks off, etc., time off between flights is set by a mandatory "rest period" by the FAA (and the airlines try to abuse and ignore this as much as possibly BTW) just a general example... another way (usually with low seniority employees), a flight attendant is "on reserve" meaning, they are on call for a set amount of days,not knowing where they will be flying to or when...when the airline calls, they are told at THAT time where they're flying to and what time they have to "show" at the airline's crew room, usually to brief with the rest of the crew before the flight, usually within two hours in the United States) In some countries, flight attendants only work on an "on call/on reserve" system let me know when the book let's out, sounds interesting!