Karlheinz Münch and I have been in correspondence about many and varied things of late. After receiving his copy of Panzerwrecks 23: Italy 3, he updated me as to the colour of the Sturmgeschütz Brigade 242 insignias. Over to Karlheinz (translated from the German original):
The colour of the 3rd battery of all assault gun divisions or brigades was yellow and not blue. The blue colour belonged to the workshops or repair units.
For this, there was also a saying of the assault artillery how to remember the colours!
“Wir rauchen gerne grün” (We like to smoke green) was the motto. The green referred to the cigarette brands Salem and Eckstein which were in green packaging at the time!
Wir (We) = white (1. Batterie)
Rauchen (Smoke) = red (2. Batterie)
Gerne (Glad) = yellow (3. Batterie)
Grün (Green) = (Stab+Stabsbatterie)
The caption does state that the information came from a prisoner, but it once again proves that you should not always believe PoW reports.