I also saw that statistic where 20 or so got called back out of 300 on the waitlist. I wouldn't read into that as a reliable indicator because it doesn't take into account the number of people who withdraw their names from the waitlist. It could be possible, though highly unlikely, that 275 people took their names off the list.
I'm trying to stay positive here and I'm definitely willing to wait it out and see if I get lucky.