As I mentioned before, when there are elites on the upgrade list, non-elites should not being offered upgrades for diminishing amounts. When there are elites with instrument upgrades being used, they should not be being offered buy up to Business offers at check in. If part of your elite package that you offer to your elites is "complimentary upgrades to business when available" it should either be that, or be worded as "complimentary upgrades to business when we exhaust all other options to get sell then to anyone at any price"
United: Do you want to upgrade for $129 ?
Customer: No
United: Do you want to upgrade for $99 ?
Customer: No
United: Do you want to upgrade for $79 ?
Customer: No
United: Do you want to upgrade for $59 ?
Customer: No
United: Do you want to upgrade for $29 ?
Customer: No
United: Do you want to upgrade for $19 ?
Customer: No
United: Do you want to upgrade for $9 ?
Customer: OK
Ladies and gentlemen, for those of you who are waiting for upgrades, the first class cabin has checked in full