Is there a way to schedule the iPads to set a custom Auto-Lock time?

Our employees use iPads in Single App mode running a custom FileMaker solution. They don't like the iPad's auto-locking while they are at work, so we disable it. However, this means the iPad screens are left on all night if they are not manually turned off. I haven't seen a way to schedule the iPads to lock or sleep at a certain time of day or to set a custom auto-lock time (like a couple hours or something). Wondering if anyone knows of a way to do something like this?

[Re-Titled by Moderator]

Original Title: Custom Auto-Lock time