We don't use CAU. We patch just like you do. Every few months or as needed for any critical updates. A node at a time. Pause/maintenance mode/patch/unpause/disable maintenance/wait for disks to be healthy and storage jobs to complete/rinse, repeat.
I seriously hate maintenance on S2D clusters. Microsoft and the hardware vendors really need to fix this. CAU works great on traditional failover clusters without cluster shared volumes. But CAU and WAC/OpenManage have never been consistent and/or safe enough for us to use on any of our S2D clusters. Hoping 2025 will be better, but I'm not holding my breath.