There have been three so far. I think there are more to come. Tonight there is both Flying Wild Alaska (discovery) and Ice Pilots (Quest) to watch if you're getting withdrawal symptoms Both are at 21.00 hrs so you could watch one of the on the +1 option.
Edit: There are it seems only three episodes of Alaskas Toughest Pilots,
Fatal Crash,
Gold Rush
Deadly Skies
So that would seem to be it next shown at 23.00 on 11th, 18th, 25th June.
Pity I would have liked to see more.