While the stock may have doubled in the last year, those hanging on for the long term are still nowhere near the pricing just prior to the crash. Those shareholders are still at a 33% loss.
The downside of early booking is you stand a greater chance of your cruise itinerary being changed, removed, or chartered, leaving you scrambling for alternatives. That said, I still book as early as I can.
You are upgrading your single device to premium in one offer, and upgrading your single device as well as adding a second device on the same account in the other offer.
You can never be sure where or who had a hand in starting the implementation of these changes. It could be the new CEO taking the hit for things started by her predecessor.