I don't think you understand the development model.
The progression goes something like this:
whiterussian -> kamikaze -> buildroot-ng -> kamikaze
Whiterussian represents the original stable branch; around RC4 development shifted from keeping whiterussian up to date to building kamikaze into a release, and the whiterussian releases suffered. RC5 was released, but the original goals for whiterussian hadn't been met, so more releases of whiterussian were planned but got preempted by the rewrite kamikaze underwent with the "buildroot-ng" branch. Buildroot-ng revolutionized the build system used to compile kamikaze.
By now, the kamikaze and buildroot-ng branches were so far ahead of whiterussian that nobody really wanted another whiterussian release (broken build system with many obsolete packages), and there was talk of backporting kamikaze/buildroot-ng into whiterussian. Ultimately it was determined that this would take more effort than writing buildoor-ng in the first place. In other words, cut the losses, release one last whiterussian and switch over to kamikaze/buildroot-ng. We didn't want to wait so long that kamikaze would be basically cut and pasted into another group's firmware and released by someone else (long story).
RC6 is mostly about cleaning out all the old tickets and fixing some known bugs with RC5. Things like the new diag system were built out of necessity -- the old code was just too hacked and tangled to maintain. While testing the compatibility of the new diag driver on some obscure models I noticed the errors with the bogomips calculations, which basically caused the router to run over 3x slower than normal, which then prompted that patch -- it was never planned. mini_fo had been planned for rc5 but got pulled out at the last minute when various issues were discovered with the file handling.
Anyways .. getting back to earlier questions ..
Automated builds of the kamikaze branch will begin shortly, binaries for pretty much all platforms with all packages. This is mostly to help us track down issues with the build system, but these snapshots will be placed online for those that wish to experiment.
I want to make it clear that I do not intend to answer any more "I bricked my router issues", a JTAG is only 4 resistors (easily under $5) and serial isn't much more, and can easily be made out of a cellphone cable. If you don't know how to recover from a bad firmware you should stay away from the kamikaze snapshots. I don't expect them to cause issues, but they are built by a script and untested on actual hardware.