One thing is for certain: AC off duty staff were the big winners with the upgrade change. AC452 had J10Y0 availability at T-60. At least 5 SE's boarded the plane (we were apparently all on standby). 8 off duty FA's in J, 2 empty seats, not a single upgrade.
At least they were kind enough to move some luggage from the overhead bins so I didn't have to store mine past row 16(!).