I am just a lowly trainman on Alaska Railroad, so I cannot really say for sure. There has been very little talk of the show recently at the railroad, which probably indicates they are at least done filming. Las time they were here filming, season two had just started airing, and the rumor was they were trying to get enough film to make two seasons. The production company is based in London, so getting them and all their gear to Alaska in the middle of the winter for filming can be a logistical challenge. I think the idea was to reduce the travel expense while still getting the show put together. A lot of it depends how Discovery feels about the show too. The production company, Windfall Films, basically makes a show, and then sells it to Discovery. If Discovery likes it and has the viewership to justify it, they buy it; if not, Windfall is just stuck with a finished show that is not wanted.