I'm not sure if this would be a hospital policy thing or a medical thing.
Is it possible to get an epidural at 9cm or does it have to be administered earlier on?
It is a medical related question, not hospitally related and depends on how the birth is planned.
This is because epidural is just an anesthesia where the drugs are injected directly into the epidural space. The time lenght of the anesthesia is determined by the type of drug used, which have different half life and so different time of action.