Are you the Registered Keeper of the vehicle (i.e. do you hold the V5C). and are your details on it completely correct? Also, what is the “docref” date shown (foot of page 2, I think)?
If none of that provides a reason for the late service of the NIP, you will have to decline any out of court offer the police may make (of a course or fixed penalty) and plead not guilty in court.
There the police will only have to prove the date of posting (probably the date of issue, 11th March) and it is presumed served on you two working days later (13th March). Your job will be to convince the court (on the balance of probabilities) that it was delivered after 20th March.
The cost of failure is high. If convicted you will receive a fine of half a week’s net income, a surcharge of 40% of that fine and costs of around £650.
Whatever you do about the speeding offence, you must respond to the “request for driver’s details” within the 28 days allowed. Failure to do so will see you commit a more serious offence which carries six points.
