They call at 7:30 AM (Eastern time), consistently. They'll call two or three mornings in a row, then nothing for a month and start over again. It's a fax machine, probing for another fax machine. I have NO connection to these people, have never heard of them, no ongoing business relationship. It's put unsolicited junk calling.
They call at 7am during the weekday in Texas which is illegal. "The telephone mailbox is full" is what the recording said when I returned the call back.