Dear maintainer(s),

The Release Team considers packages that are out-of-sync between testing
and unstable for more than 60 days as having a Release Critical bug in
testing [1]. Your package src:billiard has been trying to migrate for 63
days [2]. Hence, I am filing this bug. Your package causes autopkgtest
regression in celery, which has been fixed in unstable. However, to
avoid issued during upgrades, please add a versioned Breaks on the
version of celery in testing. Once that's added, the autopkgtest will
stop blocking the migration, because it will be scheduled with the
version of celery from unstable and celery and billiard can migrate
together.

If a package is out of sync between unstable and testing for a longer
period, this usually means that bugs in the package in testing cannot be
fixed via unstable. Additionally, blocked packages can have impact on
other packages, which makes preparing for the release more difficult.
Finally, it often exposes issues with the package and/or
its (reverse-)dependencies. We expect maintainers to fix issues that
hamper the migration of their package in a timely manner.

If you believe your package is unable to migrate to testing due to
issues beyond your control, don't hesitate to contact the Release Team.

Paul

[1] https://lists.debian.org/debian-devel-announce/2020/02/msg00005.html
[2] https://qa.debian.org/excuses.php?package=billiard