It is possible that Red Hat thinks supporting four releases at once was too much, and has
decided, but not yet announced, that it will release RHEL less frequently,
The proper way to have made that change would have been to make it effective for RHEL7.
They had already promised 18-24 month releases to RHEL5 customers. And, in fact, are still
claiming an 18-24 month release cycle in their current sales literature. Even as they blithely