Legal Question in Criminal Law in California

I'm not quite sure I understand your question.

An enhancement is additional jail or prison time added to a defendant's sentence, based on factors like use of a gun, stealing an extremely large amount of money, seriously injuring someone or serving a prior prison term.

When a person is sentenced for a crime, they get credit against the sentence for any time they have spent in custody. If the person was not in custody prior to sentencing, they would have earned any credit against the sentence.