A new reply from MORRISONS which still doesn't answer my question so I will have to define it better:

To: "emily_gyde@yahoo.co.uk"

Dear Miss Gyde



Thank you for contacting us. We are sorry that you are disappointed with the response you have previously received.



In answer to your question, there is no difference between each banking code, it may appear as one or the other depending on whether head office or the store have requested the payment.



Hope this helps.



Yours sincerely



Claire Thornton

Customer Service Department

WM Morrison Supermarkets PLC