currently the supported stop commands are:

virtctl stop --force --grace-period 0 example-vm

or gracefully if the VMI has grace-period already defined.

virtctl stop example-vm 

Trying to adjust the grace-period flag is only supported with --force, and value set to 0.

still if one would try commands like 

virtctl stop --force --grace-period 120 example-vm 

The api will accept and the VMI will be patched to have grace of 120 seconds, but even so the machine will be terminated immediately
due to some weird racefulness or some other unfamiliar bug

The expected behavior is the have the api reject calls that modify the grace-period flag when provided with --force flag as well