Late august should definitely be possible as it's about a month from now. I would also put that request in on teamworks as well! The sooner you put that request in the more likely it is to be approved! If she is unable to approve it, it's probably due to not having enough staff available for that time period but let her know how you feel about the situation! For future reference you have to apply for time off at least 21 days before that date in order to go through teamworks, otherwise you must go to your GM or ASM and ask specifically for the date/dates off! Teamworks only allows 21 days from now so it doesn't interfere with current schedules!