Spontaneous locale change on Bookworm

This morning, after a few minutes' use of my Pi5 running Bookworm,
the WiFi connection abruptly dropped. Couldn't bring it back up,
so I rebooted the access point. No luck. Then I rebooted the Pi5
and noticed something about rfkill stopping wifi in the boot messages.
At this point the last reboot was several days past, wifi hadn't been
touched or given any trouble.

Went to raspi-config and rebuilt all of the locales, still couldn't
connect. Finally I opened the system preferences and set locales,
which were already correct according to the selections shown.

The machine then proceeded to work normally, as I write this.
I've had trouble before with rfkill turning on out of the blue,
but hadn't seen the problem for a month or two and thought it
resolved.

Is this a widespread problem, and is there a fix? The fact that
it happened days after the most recent reboot seems very strange.

Thanks for reading,

bob prohaska