BeanManager#getProducerFactory return type differs between API and spec

return type differs between API and spec wording for both BeanManager#getProducerFactory methods.

In API we have
public <X> ProducerFactory<X> getProducerFactory(AnnotatedMethod<? super X> method, Bean<X> declaringBean);

While in spec (section 11.3.22 )we have
public <X> ProducerFactory<? super X> getProducerFactory(AnnotatedMethod<? super X> method, Bean<X> declaringBean);

They differ in the return type:
ProducerFactory<X> vs ProducerFactory<? super X>