As you know I've been running 2.2.4 since the first beta release, and haven't had any significant issues. Today I woke up to a mesh that is lagging quite badly. Automations, direct control of devices from the device pages, and using voice via GH are all affected. Seemingly unaffected: Bond integration, Lutron Picos and Zigbee devices they control, and Zigbee motion/contact sensors are all fine.
So looks like a Z-Wave issue.
Z-Wave details page looks boringly normal, same as yesterday and the day before, etc. No new devices added or other changes to the mesh. Every device is 40 or 100 kbps connection, except two switches which have been at 9.6 for weeks w/out causing any issues on 2.2.3 and 2.2.4.
I've PM'd you both my hub UID in case you want to look at any logs.