Here is a useful command when you need to shutdown you machine at a specific time of the day. For example after a specific event you needed to log.
shutdown -h hh:mm
Shutdown scheduled for ons 2017-04-12 22:35:00 ICT, use 'shutdown -c' to cancel.
Remark, you can can always cancel the shutdown with "shutdown -c".
Example:
shutdown -h 22:35
Get more info with "shutdown --help".
Suspend
Here is an example if you want to suspend: sudo echo 'sudo pm-suspend' | at 22:35