Similar situation to mine. I went over on a Thursday by Tuesday morning of the next week no one assigned. I had to call them twice to finally get one assigned later on Tuesday (6 days before my personal vacation overseas).
They said it normally takes 24 hours.
Over 50 nights - email
over 75 nights - email
over 100 nights - nothing
FWIW, once they assign one there name and phone number shows up on your account overview page.