So what we're looking at here, is a PC release of Horizons in a few months time, around December/early Jan if there's a delay. Then comes the Mac and X1 versions, probably around summer, or a little later. The first part is going to be airless, rocky moons and planets only for around 50$. Then, after some updates to that gameplay, some crafting elements etc, and the rest of Season two. The pass is what, 150$? Landing on atmosphere'd planets with life and cities and stuff, is much, much farther down the line. A separate expansion in fact! Season three! Then, after that, first/third person. I thought the walking around your ship etc would be first, but it seems it's years off yet. Guessing we'll be able to go to planets like Jupiter and Earth in 2017, and get first person in 2018, according to what the devs were saying on their twitch and in their Q&As today.
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Yes. ED and ED:H people will be in the same universe, same server, but the ED people won't be able to land on planets. So, figure it like Sol is now. No permit, (expansion) no pass to go to Sol. You buy the expansion, and you get clearance to go to these rocky moons and planets.