I got onto a Dash-8 with around 500 TT. Smaller outfit, not a major or regional. I know a couple of guys who went from instructing to the right seat of a turboprop - but not the likes of Porter/Jazz/Encore...more like the Calm Airs, Bearskins, CMA's and Georgians of the world. In saying that, I gave up long ago saying that things would never happen considering how few hours I had getting onto a medium turboprop. Couple other guys I worked with had 250 hours when they started...it all depended on our attitude, not how many hours we had coming into the company.
Now, back when I had a PPL with the ink still drying it was almost unheard of for pilots with less than 4,000 TT to get into the right seat of a Dash. I'd hazard a guess to say that altiplano was one of those guys.
It all depends on how many jobs there are, how many applicants there are, and what the economy is going to be doing in the next 3 to 6 months. Everyone says the days of 4,000 TT for the medium turboprops are gone...but those are the "everyones" who are yet to live through a recession or two.