A.M.
I moved back home when I was 22-24. I worked fulltime. The rule was if I wasn't coming home by 1AM I was to call...to which I had to call on the weekends and say...still out, I'm alive...coming home by xxx time or staying at so and so's.
At that time cell phones were just becoming more popular so it made it easier than when I was a 18-21. Not hard to send a quick text to let you know.
I don't think she's doing anything that is unhealthy. If she's getting up for work and taking care of her job duties and going out with her friends it's completely normal.
I don't have older kids but I do have siblings that are 10-15 years younger. I wanted to set a good example...they are now in their early to mid 20's...they follow the same rules as both live at home. It's not hard. It's respect.