So there seems to be a lot more to this than just a S47. In fact, I think he's lucky if its only S47 on the charge sheet.
As regards Fixed Penalties (or more accuratly - Penalty Notices for Disorder) - these are �80 tickets given for low level crime. A PND WOULD NOT be given for a S47 -in fact they can't be given for a S47. The only time they would be considered is if the victime refused to make a complaint, then we might consider a PND for a public order offence.
But back to your question, I agree with the madge - if found guilty, I would suspect a significant prison term for this.