Hi,

Welcome. Everyone is welcome here from the super-platinum-elite-preferred-1K to the occasional flier. Please don't feel intimidated. As long as you are sincere, you are at the right place.

The 99.99% accurate answer to your question is "No possible way". All upgrade coupons whether complementary/paid/redeemed for mileage cannot be used on free tickets and I have never ever seen any airline bend this rule ever.

The 0.01% chance is that if you have have really high status with the airline (or extremely lucky) and the flight is full you might get upgraded. And the obvious solution if you have the miles to spare; cancel this ticket, get the miles redeposited and then get a new higher-class award ticket issued (some airlines will allow tickets to be reverted back to mileage)

Or then you can try the Rudi approach - bribe'em with fine Swiss chocolates or the (immoral/maybe illegal) approach that my father used years ago with Delta which involved bribing a (disreputable) travel agent in NYC with $100-$200 and the agent would request upgrades that were instantly confirmed. When my Dad got to the airport - their computers showed that he was in B-class and they never questioned how he got there.