I just tried googling "'time to stay home' robocalls", and a bunch of other people are reporting them too. Nobody seems to know why, but what we do know is that the sender metadata is faked: the actual owners of those phone numbers are uninvolved.

(That sure does explain why a while back I got a somewhat testy voicemail from a guy wanting to know "who's been calling me on this number". Don't think I ever actually responded to him, and I'm not sure I even still have the voicemail. Well, at least now I know what to say to the next guy.)