Battery power in systray not updating

This is in fully-updated 42.2 desktop system. Desktop, not laptop, so the battery icon is reporting the status of the UPS. Perfectly fine with me.

I had a power outage a couple of days ago. When the UPS power got low enough, the computer hibernated correctly. Several hours after the power returned, I powered the system on again. According to the battery icon, the battery is at 57% and is Discharging with 15 minutes left.

That’s great and all, but it’s been showing exactly the same thing for two and a half days now.

“apcaccess status” reports the battery is at 100% with more than 20 minutes remaining.

Clearly the systray indicator is incorrect. It’s not a huge deal, except that it means the machine is using the power settings for “On Battery,” where it should be using the “Plugged In” settings as it does when the battery is fully-charged.

I’d prefer not to reboot the machine right now–I don’t expect to be able to do that for a couple of days. Is there a way to force the systray icon and the associated power software to update without a reboot? (I gather this has something to do with a service called “powerdevil” but that’s as far as I’ve been able to chase it.)