Inkpad 4 Sleep Mode

Please help me out here. I cannot figure out, how to send the Inkpad 4 to sleep mode. Don't get me wrong, when i close the case or press the power button, it shows the sleep screen.
After a while it switches off completely though and takes a minute to boot up again.

Also i cannot figure out how to configure the standby/switched off screen, it always shows the Inkpad 4 Screen.

Any ideas?