When building with --arch-all-only, the resulting .changes and .build
have the chroot arch (in my case, amd64) in filenames, rather than
'all'.

'all' is also not a sane --arch, or that might have worked. Perhaps
allow it as a --build-arch ?

Seems funny that the architectures control header is mismatched :)

cheers,
  Paul

This is defined by dpkg-buildpackage, not sbuild. Are you using dpkg
from unstable?

all is not fine for --arch, as sbuild (and dpkg) needs to know which
architecture is the chroot to resolve (build-)dependencies correctly.

Hi,

agreeing with Aurelien, this behaviour is entirely expected and will not
change.

Would you like to see something fixed in the documentation to clarify things?

Thanks!

cheers, josch