The release say it’s a hotpatch:
iXsystems is pleased to release TrueNAS SCALE 24.04.2.2! This is a hotpatch to address an issue in the previous 24.04.2.1 release where failover-related Proactive Support alerts were being triggered too often on some TrueNAS Enterprise platforms.
But my system says it will reboot when applied:
Which one is it? 
Heh.
It’s a different definition of hotpatch.
I’m sure they mean… a patch that’s bypassed the full test cycle… ostensibly because it is well targeted and surgical, and is coming in “hot”
As opposed to a patch that can be installed without rebooting, ie the system stays hot.
AFAIK, TrueNAS does not use “hot patching” in that sense, and always uses “cold” patches. Ie a full boot environment is created and booted into.
Correct; it’s always been this way, back to the earliest days of FreeNAS. I recall some discussion when 9.3 came out and it moved to a live ZFS boot pool, suggesting that updates could be applied “in place” without rebooting, and I don’t know any reason why they couldn’t be, but that’s never been the design.
