Apple's Software Update server (Policy) for Big Sur Security Updates

I undertand.

Can you push out a Jamf Helper command to automatically reboot the Mac?  We used Jamf Helper to alert users there were updates and they would install and then then require a reboot.  

You could also cache a copy of Monterey on each machine, then run a jamf policy to install Monterey. It will work and is pretty straight forward.  If you have 12hrs, you have plenty of time to reinstall the OS. It does not wipe anything and will fix any other small issues the machine has.
 You can set up a caching server so you are not downloading Monterey XX number of times.

 I used to work in a secondary school prior to my corporate job.  

At the school I would not update any labs until a break. It was then easier to just rebuild the labs anyway. We had Art, Media, Music labs etc.  Non of which needed the latest and greatest macOS to run the Apps.

All student machines were Standard users.
Staff machines were blocked for 90 days then they could upgrade them selves or let us do it. Staff were Admins.

Again, all scenarios are different and you have to work with in Policies.

I also worked at a private tertiary environment where we had 8 week terms.  Every 8 weeks we would wipe the machines and rebuild them.  Casper/Ghost worked great for PCs and the old Carbon Copy Cloner worked for Macs.  This was way back in 2002-2004

I get this as well through the GUI trying to do a mass action MDM command OS update push. Did you ever figure it out?

Computer is on 10.15.7 and just went with the latest major update it could go, and set to reboot without warning.