I'm gonna say that you got a 3.1 with a newer PCB on it. It could be that Laing is using the same PCB for both the 3.x and 3.x5 models with just some slightly different components/better windings. Last I heard, Swiftech hadn't gotten any 3.x5 yet and that they (3.x5's) actually had a 2 tone impeller.

For your original question, it looks like you'd need to move the yellow wire over to the left as you suggested.