We don't know about the release date. If there's enough of a response to this, it will be as early as possible. I'm still working on stuff I can't talk about. However, it's a given that if enough people preordered, I'd by the license right then and there. The big issue is no one has seen the GSL yet. We don't even know if this release schedule is allowed by it. If it doesn't come out for months, August might not be possible for a print book, period. My intention is to release on August 1st. I don't have enough data yet to know if that's possible, or if a Stage 1 release is even possible.
I have no intention of dropping the other lines barring the company ending as a whole. If we had a line making a lot of money, that would help the other lines immensely. That said, all the lines depend on licenses, so what I continue to support from year to year is never completely under my control. Still, I don't intend to drop them and success of any of the lines would keep the company going. Eventually, I'm going to need to start working less than 75 hours a week.
If the GSL allows it, I'll continue 3.5 and 4.0. A fifth system doesn't take THAT much longer than 4, and I have people helping me stat now. If one line takes off, I'll hire a pagemaker and that will really make the time fly.
Statting and Pagemaking are the places where the multiple systems take the most time.