When I log in to the Celebrity website cruise planner, I didn't see an option for a a drink package upgrade (My cruise included Classic Drink package.) I called them and got the them to add it and they discounted the package based on my Captains Club tier. (10%).
Just wanted to pass this along.
No additional discount for me :(.
15*8*1.18*.9 = $127.44 for an 8 day cruise.