Well, at this point, why don’t sell the other unused licence?
I can give it away at €200 (or equivalent in USD) all the below:
Live 11 Standard (Upgrade)
Upgraded from: Live 10 Standard (Upgrade), Live 9 Standard (Upgrade), Live 9 Lite
Big Band Essentials
If I got it correctly, all licences are transferred, and only somebody with an Ableton account can buy this upgrade, but let me know if I am wrong
Only an entire Live license can be transferred: all Live versions and corresponding serial numbers contained in the license will also be acquired by the recipient. This applies to Suite and upgrades; you can only transfer the whole thing.