Thanks Paul, Having googled it that has been my thoughts too. Steve PS should I put in the covering letter that as it is over two weeks it is not relevant,( original offence 1st April date on this nip 13th May) or just leave it as simple as possible.
If the NIP relates to an offence that was over the 14 days limit then it has no legal standing. Go and have a look at the Pepipoo forums for a template letter on how to respond in this circumstance. Although you've already had a (valid) NIP and you've done your legal duty, if they decide to cancel it based on the second letter and their lax admin skills then it's not your fault...