Originally Posted by ty97

There is no need to use them up. Nothing is changing to the upgrades you have in your account.

There are two earn 500-mile upgrades:
1. Be Gold or PLT and fly 10,000 miles to earn 4 500-mile upgrades. Effective March 1, 2016, that requirement will change to 'fly 12,500 miles for 4 500-mile upgrades'.
2. If you are short upgrade, you can purchase them. Currently they cost $30 each on aa.com or at a kiosk and $35 via an agent. The price is increasing to $40.

Since you have a healthy balance of upgrades, you have not had the need to buy any upgrades and will continue to not have the need to buy any upgrades so the fee in #2 did not, does not, and will not apply to you.

Put another way: Use of the upgrades in your account will continue to be free.