s6-126.96.36.199 is out.
It fixes a race condition that could lead
to miss back-to-back state changes. (Sorry about that.)
Unfortunately, the fix required change to some externally visible ABI,
so it enforces a major version bump.
External binaries dynamically linked against libs6.so.2.5 need to be
when you upgrade to s6-188.8.131.52. Binaries statically linked against
only need to be rebuilt to benefit from the bugfix.
More bug-reports welcome.