I'm not sure what the benefit of this is, as the car tells you when it has downloaded an update and is ready to install. It's unlikely someone would want to install an upgrade while they're away in case something goes wrong.
If it arrives in the evening, you may want to accept then instead of finding out in the morning the update it ready.
You may not be able to tell by here on TMC, but many of us are impatient and like to try the updates out as soon as possible.