Went out to move the bikes around in the garage so neighbor can store his bike in our garage for the storm. Noticed when I turned the key on the CBR250R one notch too far that it didn’t produce that characteristic “whine”, and then clued in that the instrument cluster was dark.
Multimeter in hand checked the battery and sure’nuff it was showing 5.6 volts – a little low to run the bike. Ok, one issue at a time. Hook the bike up to the battery tender and get it charged back up.
Battery measures 13v fully charged, so that suggests the problem is elsewhere. Will climb all over the bike in a few days based on advice from the helpful folks at the CBR250 forum, and will try to isolate the issue.