Originally Posted by
CPMaverick
It was 7 years ago now but I used to fly ANA regularly to Japan with UA status, and 90% of the time they gave me a free upgrade to Premium Economy (which is a LOT nicer than Delta's C+). It wasn't the day of travel either, after booking I was able to select Premium Economy on the ANA website.
I believe you are only supposed to get this automatic upgrade if flying on a Y (unrestricted economy) fare, or if you have ANA status.