util-linux 2.25.2-4.1+devuan1 breaks sysvinit 2.88dsf-59.1 (Release: testing)
Debian has updated the sysvinit packages (initscripts, sysv-rc, sysvinit-core, sysvinit-utils), which are currently still being merged from the Debian repositories, from 2.88dsf-59 to 2.88dsf-59.1. This introduces a dependency on mount (>= 2.26.2-3). Devuan ships util-linux 2.25.2-4.1+devuan1, thus breaking the dependency.
An immediate remedial action could be for Devuan to ship sysvinit 2.88dsf-59 (it looks like it is already imported into git, but disabled in the build and thus not yet shipped), to maintain compatibility with util-linux 2.25.2-4.1+devuan1.
Another approach would be to update util-linux to something like 2.26.2-3+devuan1. Though probably considerably costlier, from my non-expert POV this looks like the better approach, if only to move somewhat unrelated utility binaries from init system packages to more general system utility packages.
AFAICT this issue currently affects only Testing, not Jessie. (Under reserve of any potential future backports to Jessie.)