Originally Posted by
Away from YYZ
It depends on how much over and beyond you are willing to bet on your chances in aerolotto, the game you can't lose if you don't play.
if the chances seems slim (e.g. J2R0) you might as well cancel it and buy a Tango or Tango+ (if you still want to place your bet)
Agree, AC website doesn't make it clear or somewhat misleading about "immediately upgradeable".
But FTers knows better. 
Most anyways
You bought an economy ticket, what do you really expect? That everyone who buys lat, automaticaly gets J... why offer J at a higher price then? Does that not seem silly to you?
You paid a lot for a chance to upgrade automaticaly, but most of the value in your ticket is that you can cansel it any time. The auto upgrade over the 7 day SE window just gives you a better chance to get the seat, thats all. As other have said, next time select the box ''display upgradeable fares'' and the site will tell you straight up if you can upgrade or not.