Adr network class 1 royal mail chelmsford

A very specific question!

According to the Royal Mail's website, the AD (Address Data) network class for the postcode CM1 (Chelmsford) is as follows:

This means that all postcodes within the CM1 area, from CM1 1AA to CM1 1ZZ, are classified as Class 1.

Here's a breakdown of the Royal Mail's AD network classes:

Keep in mind that these classifications are subject to change, and it's always a good idea to check with Royal Mail or a reliable source for the most up-to-date information.