From the main menu, select Customer Order
Setup, then Delivery Options Maintenance
Select the Service Charges radio button.

Select the Carriage Band radio button

And then click into the Standard UK Delivery
You should now enter the delivery charge
per programme against Band A.
Don't forget to click on Update to save
your changes.
This process should be repeated for each Band
and Service you will use, such as for international orders.
When setting up these postage charges up via 'additional postcodes' (as seen on the first image), with the default settings within the system configuration tab, the value you input here as the 'new charge' is added on top of the original postage value rather than amending it completely.
For example, if the standard delivery rate is £3.50, and for a selected postcode you input a new charge of £6.50, these customers would then be charge £10.
However, you can change this so that the 'new charge' represents the entire postage charge that these customers will incur.
This can be done by going into File Maintenance > System Configuration > Web Specific. If you scroll down to near the bottom, you should see the following option:
Select Charge instead of Additional.