I can see the broad strokes for other characters by combining where they are by 6x02 and what we can infer from the trailers, even without leaks. And whilst what you mention will happen, and will obviously flesh out this season, apart from establishing Nu-Jon, I'm not sure what else he has to do. Take Wildlings and Davos and march, probably towards Winterfell. I have a feeling, after next week's Jon scene(s), they'll drip feed it before a very Jon/Ramsey lead episode.
In terms of Jon's parentage, I would hope he would learn it this season. Unless they establish he can warg, and interact with weirwood.net and thus Bran, I'm inclined to think it'll be through a human character. They seem to want to shy away from the other Stark children being wargs, so my monies on Littlefinger (purely based on THAT look he gave Sansa last season in the crypt; he knows stuff).