Well, when I was booking our March cruise in January, I called Celebrity to confirm that sparkling water and juices would indeed be included if we chose "all included" and they said YES. Either the rep was reading the info off of their website, or their internal documents also had Zero Proof included in Classic at that time (1/20). I've done my due diligence so I fully expect our cards to be coded according to how the package was sold to me.
The cost of going with AI vs cabin only was actually a couple of dollars less than adding separate gratuities, wifi, and zero proof package, so it was a really good deal to get a Classic package for less than the cost of Zero Proof. If they make me pay for bottled water after all, I won't be happy, but we'll still be ahead.
Re grandfathering, should be fairly easy to implement as their database includes the price and category for each drink, among other things. The passenger card is what decides if that drink will ring up as a $0 or some other value. Each card could be easily coded to include or exclude whatever is needed in any combination, not just current packages (Premium, Classic, Zero Proof, or None), but unlimited versions of each. I really hope that's how things already are and it won't be a fight for any of us to receive what we purchased.