A 1.48 beta 5 weeks after 1.47 ships seems doable. That would be about August 8th, and then the release 3 weeks later, or about August 29.
The 1.49 release then would be back on schedule for the first Monday in November.
5 weeks is not enough to start something big, I'd consider 1.48 to be little more than a bugfix version, a 1.47.1 in other words.
Part of the reason for having frequent releases is so that they aren't 'something big'. I think including Boost.Move is enough to justify a release. And it might also include the new version of the unordered containers.
I understand the theory, but I like the routine of planing in 3 months cycles. Uncomplicated and I know when the release branch is going to be closed when the calendar does not work. A release after 5 weeks is likely to force me to maintain 2 versions. Frankly, I'd have preferred to wait a week more and get Boost.Move into the 1.47. Christophe