I just got my Big 4 invite immediately after turning on my phone after a TATL flight....
I've heard some folks trying to do challenges with a week or two backdate not having any luck with it this year.
They backdated my FastTrack promo 2 years ago when I used it to qualify for EXP.
They probably wont even let me use this again, they email footnotes say once every 5 years.
AAdvantage stinks.