The question in Server Fault is closed too, but I miss the entries who and why it is closed.
Is there a bug in the migration process?
Jeff has said that multiple migrations are not supported, so this bug will probably not be fixed.
It is no longer possible to "multiple migrate", that is, send a question from
We disallow migration of already migrated questions so you can only migrate a question once.
(Diamond mods can still manually multiple-migrate but it is frowned upon.)