Well if your downpipe+ exhaust had lots of oil in it (which it probably did, i know mine did 2when the turbo crapped out) it should take quite a while for it to stop smoking, i have heard up to 2000 miles
mines at about 1000 and is still smoking
I don't think that is a big problem yet.
Ps - Don't let rotaries sit for long periods of time, they don't like it at all.