Thanks folks,
The Yorkshire tastes fine, 2 bags in a 16oz cup (500ml) is my usual brew (leave the bags in till the cup is empty... of course). It came out a bit weaker than I'm used to but the bag contents seem a bit lighter than my usual brand of Red Rose, however the taste was similar.
As above B3 or maybe a C2 is what I see but my oat milk doesn't play as nice as the real stuff, passable taste but it doesn't stay mixed as well as the real stuff.