MONTREAL — Concluding a Canada-U.S. softwood lumber agreement in the coming weeks remains uncertain but there is headway on the thorny trade dispute, the head of lumber producer Tembec suggested Wednesday. “We understand that some progress is being made and that the differences of the gap between the two countries has narrowed,” CEO James Lopez said during a conference call to discuss its third-quarter results. The Montreal-based company said its net income nearly doubled to $17 million in the period ended June 24. Lopez didn’t explain what his outlook is based on but said it’s difficult to predict the timing and structure of a new agreement. “Hopefully we can get that outcome in short order but we all know, those of us have been around this for a long time, it’s very unpredictable.”