You can see them as "Opcion Upgrade" even before you can even ask for an upgrade with coupons i think...
My friend and I went to LIM about a week ago, he has only Gold Status and in our way back i told him try to ask for the upgrade with your coupons and if to many people before you i will give you one of mine. This was on the LIM SCL where sometimes is quitte empty and some not.
Well he went online 48 hours before the fly and i mean 48... He was updating the page all time, when he was able to check inn he ask for the upgrade and got 3rd place, before him there was 2 opcion upgrades........ Well finaly where about 10 seats free and he was about 9th so i used my coupons anyway to be sure