CarefulBuilder14 wrote:If I were to book a domestic AA-operated flight with BA Avios, would my Citi AA Platinum still give me the free checked bag?
Would the answer be specific to BA/AA, or is there a nearly-universal practice among airline alliances for this?
It's specific to the benefit from the card and not necessarily on any generalization about alliances. I'm not familiar with that card and how it works with AA and can't comment on it.
With the United MileagePlus Explorer the free checked bag benefit is supposed to only be provided when you pay for the United ticket with the UMPE card. However, I've received the benefit when using other payment methods, redeeming reward travel, etc. It seems as long as I have my MileagePlus account linked with the UMPE card and that the reservation is associated with my MileagePlus account number that I get the benefit regardless of how the reservation is booked or paid for. I haven't booked on United via a partner but, again, if the reservation had my MileagePlus number associated with it I would expect to receive the benefit based on past experience given how they determine if I'm eligible for the free checked bag.
You might have better luck getting answers on a site like FlyerTalk.