That's been my experience ordering from Aliexpress with their free shipping, 4 - 5 weeks. I think I once had something arrive in 2 weeks and I was really surprised.
I've had 4 days once. It just depends on when the bags get full enough to send on, and how soon you get relabeled once its in the country if they're using a consolidator that does that.
Im amazed at how cheap packaging materials must be for them over there, the cost of some of the items delivered to me here wouldnt buy the bubble envelope locally. Tempted to see if I can order some from there rather than using blackwoods.