Ok, this book is one i picked up at an airport in Hawaii 2011. Its a SciFi romance that I think is intended for YA as the main characters were between 15-22. They were living on a spaceship with the Heroine sneaking through the vents. I’m pretty sure they rotated on a 10 hour schedule with the week starting over at 100 hrs.
Please help me, this book was so good it haunts me!
I think this is Inside Out by Maria V Snyder
Maybe GLOW by Amy Ryan?
It’s probably not this one unless you bought it used, but it sounds a lot like Annabelle and Edgar Johnson’s An Alien Music.