It is the way a cowboy says "yes".

OK, but seriously folks, it is a Y fare often restricted Y that gives you a J/F seat confirmed at the time of booking without using points, co-pays or e-upgrades. Subject to loss of that seat if you change flights or if you experience a delay etc., forcing you to. Earns the 1.5 EQM as it is still a Y flight.

I find to leisure destinations they can be good, e.g Las Vegas and Honolulu and as part of a connection, horrendous, e.g. YYZ-MIA (connecting onward) they add all sorts of complex rules and don't save a nickel over, at times, full J.

Try doing a route on AA.com discounted Business as the rule and select show by fare vs. schedule. Then look at the fare rules and see if has Y and UP in the code, like Y26UP or YUP6 etc. It is hit or miss.