Zwave routes disappeared overnight (got them back but don't know why it happened)

This morning at about 4am I noticed that my hall lights didn't come on, though the green indicator light on the motion detector flashed. I checked my zwave details page on my main hub and probably 80% of my zwave devices no longer had routes! I shut the hub down, powered it off for a minute or so, and powered it back on. It looks like that has resolved the immediate issue but I am concerned I don't know why it happened.

I checked the logs and can't see anything obvious. No zwave busy message, no unusual or excessive device activity from zwave devices, etc. However, I do reboot my hub every Sunday morning and it appears the reboot was in the suspect time period, somewhere between about 1:30am and 4am. The reboot is at 3:15.

I made a whole bunch of changes to my HE environment yesterday so it's a bit difficult to say if I introduced something that caused the issue. Here's what I recall doing:

I moved a bunch of CPU-intensive activity OFF my main hub onto a secondary. Most of this was rules that repeatedly ping my iphone to see if it's still there. (Yeah, I know... life360. But apparently tracking household members isn't acceptable.) I don't see how this could possibly have done anything but help the primary hub.

I excluded and removed a couple of Fibaro flood sensors. They were not paired s0 but they were also not reporting temperature. I did not re-add them since they're a pain to include without security. I excluded and re-included a strips water sensor because it wasn't reporting temperature. And I added a couple of zigbee leak sensors to replace the Fibaros. After removing and adding zwave devices I always check the zwave details page to make sure I haven't introduced any obvious issue, so I know it was clean then. The strips sensor is reporting temperature and seems to be working fine. I do generally practice good zwave hygiene though I have a couple of outlier devices that are a bit weak.

I updated the hubs from 2.3.0.118 to 2.3.0.119. I did this mid-day and everything looked good afterward. There's nothing in the release notes about any zwave changes, only fixes for database corruption. I haven't seen any evidence of that, nor can I explain why it would have affected zwave routes and nothing else, so I have to think the .119 upgrade was a coincidence, but who knows.

Any ideas or additional troubleshooting steps?

I lost 7 devices (motion sensor, lock, and 5 shades) in similar fashion when upgrading from 2.3.0.124 to 2.3.1. This was prior to performing the optional Z-Wave firmware update to 7.17.1. So that makes that similarity suspicious. I also hadn't done much to my hub the days prior to the firmware update.

They also haven't come back. I have since completed the Z-wave update to 7.17.1. Fingers crossed they also come back without repeating inclusion.

My post was an old one but have you tried shutting down the hub safely, removing power (preferably not by pulling out the micro USB connector), waiting a minute or so, and plugging it back in? This allows the zwave radio to fully power down and reset.