Originally Posted by
Hagbard Viking
Platinum and Gold members earn four upgrade "stickers" (now electronic) for every 10,000 miles BIS regardless of class. Each sticker is good for upgrading 500 miles of domestic flying. "Miles towards elite upgrades" shows how many more BIS miles are needed to earn the next set of four stickers, "upgrade account balance" shows how many stickers are available to use for upgrading.
Actually, "Miles towards elite upgrades" shows how many BIS miles have been flown since March 1. Every time that the fifth digit to the left of the (unshown) decimal place changes, AA gives you 4 more 500-mile electronic upgrades. The mileage does not, however, go down (until it starts over on March 1). So you have to subtract the mileage shown from the next 10,000 mile increment to get how many more BIS miles are needed to earn the next set of four stickers.