Hey Gentle ,
   We don't have a final plan yet but we will most likely migrate peoples' remaining time on Butter-Bot to BX based on both how much time they have left and whether they were early adopters. So if someone was among the first to sign up and they maintained a current sub throughout they may end with a free migration to BX of their remaining time (or perhaps something better) while other subscribers will be subject to partial credit of their remaining time on the new platform on a scale of antiquity and constancy. We will work with the community to come up with a fair transition program once we have finally tallies on everything. Migrations will be completely optional and we will maintain development on Butter.

You have to keep in mind that BX costs us several times more per customer in terms of maintenance, development, hosting, etc., than Butter does (because it's so much more feature rich) so we have to be very careful on how we scale this as to maintain long term viability.

I hope that answers your questions :=).

Pablo.

PS: As a general update, we are about 80% done with BX. As I mentioned before, we have some prominent members of the community Beta testing it now but we have run into a snag in terms of needing some extra Ruby developers both to help us complete the software, but more importantly because our current team would not be able to support the debugging and growth needs of the thousands of users the launched platform should reach, so we are trying to get that done with and then pump out the software as fast as possible. Getting a qualified person is quite harder than you might believe for a start-up but we will hopefully get there soon .