I work 4-midnight 5 days a week, I can't go home until I am relieved, like twice the week before last my relief was 1 hour late. I have had them just no show and if I was lucky my boss got someone else to show up half way thro the next shift, so 4 more hours. Worst case I am there till 8 am when the day shift comes on. I can understand where your coming from, a lot of it is what kind of job are you working, some jobs should be x-y and you can leave after, some jobs are x to y or x to when your relieve shows up, usually you know which is which before you get the job. So basically, I am no help.