At Adepticon, people are able to stand around and chat with game designers about the upcoming projects they have been working on. But that's a pretty rare thing, in general. Not everyone can make it out to a show. And then, the designer might be busy or such. Panels are one way you can find out about stuff, but you still sort of have to be there. It's a good thing, then, that the internet is a thing (since, you know, I also work there). Designer Michael Shinall recently did an Ask Me Anything (AKA - AMA) on Reddit.
Many of the questions focused around how Second Tide will fit in with the original version of the game and its expansions. Addressing those, it was said that there will be an add-on to the Kickstarter that will basically be sold at cost which will give players all the material they need to update their old figures and game (the pack will have new dashboards, tide decks, Kraken and Sea Dragon cards and tiles and so forth). Second Tide will also be its own stand-alone game. So if you don't have the original Rum & Bones, you don't have to get it in order to play.
Check out the full AMA for full details.