Hi shortshrift
It will be interestng to see if / how this offence has been recorded and if it was recorded then how was the crime report finalised.
Basically, if an offence of assault was recorded (prob ABH), then some manager would want it detected by a charge, caution or summons etc (only for SMT's pie-charts and not for the good of society). It may be that the offender was dealt with for a public order offence in the absence of your complaint but then you should have really been informed if that were the case. But do give the relevant police farce a call, it is a common occurrence etc