Originally Posted by
Adam1222
This question is confusing. All the legacies except American offer upgrades to all elites on a space available basis. How frequently you get it will depend on your status and the routes you fly/time and day of week
Yes, but I think the question is asking which airline gives them most easily, all other things being equal.
For example, if you have the 50,000 mile status on UA, DL and AA, and you fly LAX-JFK on each at the same day and time, which airline is most likely to upgrade you?