I can confirm that candlepin-4.4.12 causes serious issues with the whole foreman/katello system including issues during upgrade to 3.11/4.13. We have ran into the same issue in Upgrade from 3.10.0/4.12.1 to 3.11.1/4.13.1 makes foreman unusable. Downgrading candlepin and restarting tomcat seems to solve the problems.
