WWII Southern Command

Can anyone help re a WWII Southern Command Formation Insignia query please? As the Southern Command (shield) badges were all unit colour specific, i.e., Infantry, Royal Engineers, etc, I had assumed that no AOS would need to be worn? But, I have just seen an image on the www of a WWII Battle Dress jacket with Royal Artillery cloth should titles, RA Southern Command shields and below it RA AOS on both arms. I cant upload the image on here (!) but can anyone shed any light on the Southern Command and AOS please? Thanks, Ken 👍

[badjez]

Arm of Service strips were worn army wide, worn in accordance with Army Council Instructions. The Southern Command formation signs were worn to show the Command, the colouring being a bonus in addition to the AoS strip.

Stephen.

Stephen, that's a brilliant answer.
Thank you very much.
Ken ��