Millions of Violations
If your SonarQube instance contains a lot of coding rule violations, the migration process can take very long (up to a few days).
Therefore, it is highly recommended to directly migrate to version 3.7.2 that speeds up this migration process.
Information provided by the Update Center is erroneous while upgrading from 3.5.X to 3.6
Please check rely on the plugin compatibility matrix before upgrading.