I am having the same issue. You can see my post is the last reply with no answer in the linked thread
When I first got the car running on the single set up, no leak at all. about 2-300 miles in I noticed it was wet, then at about 500 miles in, it was smoking pretty good.
At first I thought it was maybe my lowside PCV causing to much crank case pressure (at the time I had headports blocked with stock PCV in place lol) so I bought a pcv delete and now vent both hi and low side VTA..... turbo still leaking like a pig.
just ordered a oil restrictor from summit yesterday so we will see if that does the trick.
drain is an atp turbo 10an fitting to a 10an line, with a 10an fitting welded onto the stock return fitting. maybe we need 12an...idk
its interesting if you google leaking oil feed precision turbo, the only people I can find with the same issue as me are n54 cars....