I remember my son's ALO calling to hear if TwinA had "heard the news." TwinA said, "What news?" and the ALO said he'd call back in a few days. So we KNEW!
Son had the status online change to "Appointment Offered". 3 days later, BFE. That night at the high school football game we told the ALO. So there's lots of different possibilities of how to be contacted.
I had to check online and was shocked when I saw Appointment Offered. Today the BFE came in and was postmarked March 25th since I have mail forwarding (not as big as I thought it would be but still big enough to take up the whole mail slot).