Just checked, we used to use the wreath on all Nomads, around the same time we went 531-725 we trialed the shield one as this one has, then the very late 725 went back to a wreath of Thorns. So the head badge isn't a definitive way to tell either, however this one is 725 for sure as it has a 27.2mm seat post and all 531's were 27.0mm, the tubing was also embossed as 725 (which I can't show you as its now painted).
Hope this clears any confusion, apologies for the minefield I seem to have created