A FlyerTalk Posting Legend
Join Date: Sep 2012
Location: SFO
Programs: AC SE MM, BA Gold, SQ Silver, Bonvoy Tit LTG, Hyatt Glob, HH Diamond
Posts: 44,347
A new *A rule requires "same flight". I haven't encountered it anywhere. And while I could see AC requiring a UA*G be on the same flight as their guest (since they only get reimbursed for entry in accordance with *A rules), I don't think their intention would be for it to apply to an AC*G.
And I certainly don't think they've actually done anything, given it isn't mentioned on AC's site (whereas UA's site does have that blurb).