The actual ORRCA rules on motors say:
13.5 Electric – Any commercially available 13.5t motor on ROAR, BRCA approval list
It's my understanding that the D3.5 is no longer on the ROAR list, and I think was never on the BRCA list. AARCMCC have given grace period until the end of 2014, but I'm not aware of an ORRCA announcement to that effect. That would have the D3.5 not being legal unless I'm interpreting the rules incorrectly (which is quite possible).