Nope, definitely not coming out of the drain, but from the seals. I lifted the dust seal (which is covered in oil), there's oil laying on top of the fork seal and I can see it dribbling down the fork leg, caliper and disc. Yes, I know I'll need new pads as well as a lot of degreaser to clean the disc off too. The only thing I can think of is the fork leg is pitted at the very bottom where the seal will be when there is no weight on the bike so the fork leg is fully extended but when being ridden the seal is higher up the leg and seals at that point. I'm thinking that if I can see any damage on the leg when I get it apart to fit the new seals, I fit the seals with a spacer under them so they bear on a different area of the leg.