I forgot to mention one important cause of the bug. My (standalone) APs are all in Manhattan and the noise is incredible. You can detect over 300 radios fighting for 2.4G and 5G channels. What I presume happens is that ChannelFly becomes overloaded, spikes the CPU, and after a certain threshold of spiked CPU the kernel forces a reboot.
Without seeing the source of the ChannelFly logic, I cannot say for sure, but when ChannelFly is disabled, I have absolutely no reboots. If I enable it, I am guaranteed to have a reboot occur within 24 hours. This would explain the “random” or “sudden” experience of reboots: since I believe that the CPU spike is based on reactions to outside noise from ChannelFly.
If you’re operating in a reasonably quite environment, this bug would probably not present itself.